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<rfc xmlns:xi="http://www.w3.org/2001/XInclude"
     ipr="trust200902"
     docName="draft-marques-asqav-compliance-receipts-05"
     category="info"
     submissionType="independent"
     version="3">
  <front>
    <title abbrev="Compliance Receipts Profile">Compliance Profile of Signed Action Receipts for AI Agents</title>
    <seriesInfo name="Internet-Draft" value="draft-marques-asqav-compliance-receipts-05"/>
    <author fullname="Joao Andre Gomes Marques"
            initials="J. A."
            surname="Gomes Marques">
      <organization>Asqav</organization>
      <address>
        <postal>
          <country>Portugal</country>
        </postal>
        <email>joaoagm90@gmail.com</email>
      </address>
    </author>
    <date/>
    <area>General</area>
    <keyword>AI Agents</keyword>
    <keyword>Audit Trail</keyword>
    <keyword>Compliance</keyword>
    <keyword>EU AI Act</keyword>
    <keyword>DORA</keyword>
    <keyword>NIST AI RMF</keyword>
    <keyword>Colorado AI Act</keyword>
    <keyword>HIPAA</keyword>
    <keyword>NYDFS</keyword>
    <keyword>CIRCIA</keyword>

    <abstract>
      <t>This document defines a multi-jurisdiction compliance profile of the signed action receipt format used by AI agents to record machine-readable evidence of access-control decisions. The profile binds receipt fields to two regulatory surfaces: on the European Union side, Articles 12 and 26 of the EU AI Act (Regulation (EU) 2024/1689) and Article 17 of DORA (Regulation (EU) 2022/2554); on the United States side, the NIST AI Risk Management Framework, the Colorado AI Act, the Texas Responsible AI Governance Act, the New York Department of Financial Services Cybersecurity Regulation (23 NYCRR Part 500), the HIPAA Security Rule, SEC Rule 17a-4, and the Cyber Incident Reporting for Critical Infrastructure Act of 2022 (CIRCIA). Working entirely within the existing wire format, canonicalization transformation, and signing algorithms of the underlying receipt format, the profile tightens a subset of the OPTIONAL fields to REQUIRED, imposes a retention floor, and requires at least one timestamping anchor (RFC 3161 or OpenTimestamps). It registers OPTIONAL extension fields for risk and incident classification, cross-agent envelope binding, per-action freshness and integrity, build provenance, threat-framework taxonomy, and server-built enforcement attestation, each subject to false-attestation guards where applicable, and registers receipt type namespaces for passive-telemetry and result-bound observation receipts. The full field set and its normative requirements are defined in the body of this document.</t>
    </abstract>
  </front>

  <middle>
    <section anchor="introduction"><name>Introduction</name>
      <section anchor="profile-not-fork"><name>Profile, Not Fork</name>
        <t><xref target="ACTA-RECEIPTS"/> specifies a generic, signed receipt envelope for recording machine-to-machine access control decisions made by AI agents. Section 2.2 of <xref target="ACTA-RECEIPTS"/> defines a common payload field set in which all fields except <tt>type</tt>, <tt>issued_at</tt>, and <tt>issuer_id</tt> are OPTIONAL. Section 5.7 of <xref target="ACTA-RECEIPTS"/> introduces hash chaining (<tt>previousReceiptHash</tt>) inside an optional Commitment Mode extension. <xref target="ACTA-RECEIPTS"/> does not define receipt retention, does not require timestamping anchors, and does not bind to any regulatory regime.</t>
        <t>This document is an additive overlay on <xref target="ACTA-RECEIPTS"/>: it constrains fields the upstream draft leaves OPTIONAL, fixes their values where regulation requires, and registers a set of extension fields with reserved names spanning regulatory classification, cross-agent envelope binding, per-action freshness and integrity, build provenance, threat-framework taxonomy, and server-built enforcement attestation. The full extension-field set is defined in <xref target="extension-fields"/> and the sections that follow it. A Compliance Receipt remains a conformant <xref target="ACTA-RECEIPTS"/> receipt. Field references use upstream field names rather than section numbers, to reduce maintenance hazard if upstream re-numbers in a future revision.</t>
      </section>
      <section anchor="scope"><name>Scope</name>
        <t>This document fills the regulatory binding gap on two surfaces. Section 5 binds the receipt to European Union obligations: Article 12 (record-keeping) and Article 26 (deployer obligations) of the EU AI Act, and Article 17 (ICT-related incident management) of DORA. Section 6 binds the receipt to United States obligations: the voluntary functions of the NIST AI Risk Management Framework, the deployer obligations of the Colorado AI Act and the Texas Responsible AI Governance Act, the audit-trail and incident-reporting obligations of NYDFS Part 500, the audit controls and documentation retention of the HIPAA Security Rule, the broker-dealer recordkeeping requirements of SEC Rule 17a-4, and the covered-incident reporting requirements of CIRCIA.</t>
        <t>The bindings are written from the Deployer's perspective, where Deployer is used in the regime-specific sense (Article 3(4) of <xref target="EU-AI-ACT"/> for EU bindings; Section 6-1-1701(6) of the Colorado Revised Statutes for Colorado bindings). Where another statute uses a different term (Provider, Financial Entity, Covered Entity for HIPAA, Covered Entity for NYDFS, Broker-Dealer for SEC, Covered Entity for CIRCIA), the binding section names the term as the source statute uses it.</t>
        <t>A verifier that implements only <xref target="ACTA-RECEIPTS"/> can cryptographically validate a profile receipt but cannot attest the additional compliance bindings of this document.</t>
      </section>
    </section>

    <section anchor="conventions"><name>Conventions and Definitions</name>
      <t>The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 <xref target="RFC2119"/> <xref target="RFC8174"/> when, and only when, they appear in all capitals, as shown here.</t>
      <t>The following terms are used in this document.</t>
      <dl>
        <dt>Action:</dt>
        <dd>An operation performed by an AI agent that is subject to a policy evaluation. Examples include a tool invocation, an external API call, a write to durable storage, and the issuance of an irreversible instruction to another system.</dd>
        <dt>Action Receipt:</dt>
        <dd>A signed envelope conforming to <xref target="ACTA-RECEIPTS"/> that records the policy evaluation result for a single Action.</dd>
        <dt>Compliance Receipt:</dt>
        <dd>An Action Receipt that additionally satisfies the requirements of this profile.</dd>
        <dt>Deployer (EU AI Act):</dt>
        <dd>As defined in Article 3(4) of <xref target="EU-AI-ACT"/>.</dd>
        <dt>Deployer (Colorado AI Act):</dt>
        <dd>As defined in Section 6-1-1701(6) of the Colorado Revised Statutes, as enacted by <xref target="COLORADO-AI-ACT"/>.</dd>
        <dt>High-Risk AI System (EU AI Act):</dt>
        <dd>As defined in Article 6 of <xref target="EU-AI-ACT"/>.</dd>
        <dt>High-Risk AI System (Colorado AI Act):</dt>
        <dd>As defined in Section 6-1-1701(9) of the Colorado Revised Statutes, as enacted by <xref target="COLORADO-AI-ACT"/>.</dd>
        <dt>Financial Entity:</dt>
        <dd>As defined in Article 2(2) of <xref target="DORA"/>, for entities listed in Article 2(1).</dd>
        <dt>Covered Entity (HIPAA):</dt>
        <dd>As defined in 45 CFR 160.103, namely a health plan, a health care clearinghouse, or a health care provider that transmits health information in electronic form in connection with a covered transaction.</dd>
        <dt>Covered Entity (NYDFS):</dt>
        <dd>As defined in 23 NYCRR 500.1(e), namely any person operating under or required to operate under a license, registration, charter, certificate, permit, accreditation or similar authorization under the Banking Law, the Insurance Law or the Financial Services Law, regardless of whether the covered entity is also regulated by other government agencies.</dd>
        <dt>Broker-Dealer:</dt>
        <dd>As defined in section 3(a)(4) and 3(a)(5) of the Securities Exchange Act of 1934, subject to recordkeeping under <xref target="SEC-17A-4"/>.</dd>
        <dt>Covered Entity (CIRCIA):</dt>
        <dd>As to be defined in the final rule promulgated under the Cyber Incident Reporting for Critical Infrastructure Act of 2022. Pending publication of the final rule, the term is interpreted in accordance with the statutory definition at 6 U.S.C. 681 and CISA's notice of proposed rulemaking.</dd>
        <dt>Audit Pack:</dt>
        <dd>A bundle of Compliance Receipts, the chain commitments that link them, the public verification keys, the trust anchor metadata, and the regime mapping required by Sections 5 and 6 of this document, packaged for delivery to a regulator or auditor.</dd>
      </dl>
    </section>

    <section anchor="relationship"><name>Relationship to ACTA-RECEIPTS</name>
      <t>This profile is an additive overlay on <xref target="ACTA-RECEIPTS"/>. It does not modify the envelope, the canonicalization rule, the signature object, or the algorithm registry of <xref target="ACTA-RECEIPTS"/>.</t>
      <t>The following normative statements apply.</t>
      <ul>
        <li>Implementations of this profile MUST produce receipts that are cryptographically verifiable by a conformant <xref target="ACTA-RECEIPTS"/> verifier under the canonicalization rules (JCS, <xref target="RFC8785"/>) and the signature scope of <xref target="ACTA-RECEIPTS"/> Section 5.6.</li>
        <li>Implementations of this profile MUST NOT introduce new top-level fields in the signed payload that conflict with names reserved by <xref target="ACTA-RECEIPTS"/>.</li>
        <li>Implementations of this profile MAY use any signature algorithm permitted by <xref target="ACTA-RECEIPTS"/>: EdDSA (Ed25519, mandatory-to-implement, <xref target="RFC8032"/>), ES256 (ECDSA using P-256 and SHA-256, <xref target="RFC7518"/>), and ML-DSA-65 (<xref target="FIPS204"/>).</li>
        <li>Where <xref target="ACTA-RECEIPTS"/> marks a field OPTIONAL and this profile marks the same field REQUIRED, the stricter requirement applies to Compliance Receipts.</li>
      </ul>
      <t>A receipt that fails any MUST clause of this profile is not a Compliance Receipt. It MAY still be a valid <xref target="ACTA-RECEIPTS"/> receipt.</t>
      <t>This profile differentiates from <xref target="ACTA-RECEIPTS"/> on three axes: mandatory hash-chain linkage (upstream Commitment Mode is OPTIONAL), mandatory anchoring with RFC 3161 or OpenTimestamps (both RECOMMENDED; upstream lists Sigstore Rekor in its Implementation Status appendix as an OPTIONAL temporal anchor), and a retention floor tied to specific regulatory articles (upstream is silent on retention).</t>
    </section>

    <section anchor="canonicalization-scope"><name>Canonicalization Scope</name>
      <t>This section is normative. The canonicalization rule itself (JCS, <xref target="RFC8785"/>) is inherited unchanged from <xref target="ACTA-RECEIPTS"/>; this section bounds the inputs the rule is applied to, so that the cross-implementation byte equality on which the hash chain of <xref target="hash-chain"/>, the anchor scope of <xref target="anchoring"/>, and the cross-agent binding of <xref target="counterparty-binding"/> all depend is achievable in practice.</t>
      <t>IEEE-754 floating-point numbers MUST NOT appear in the canonical form covered by a SHA-256 digest under this profile. Callers MUST serialize numeric values that are not exact integers in the IEEE-754 safe integer range (the closed interval from minus (2 to the 53 minus 1) to plus (2 to the 53 minus 1) inclusive) either as JSON strings or as integer-rational pairs (numerator and denominator as JSON numbers within that safe integer range) before the canonicalization step.</t>
      <t>Rationale: Section 3.2.2.3 of <xref target="RFC8785"/> specifies, by reference to Section 7.1.12.1 of ECMA-262, a byte-stable serialization that in principle covers all IEEE-754 double-precision values, integer or fractional. In practice, several widely deployed JSON serializers do not implement the ECMA-262 Number-to-String algorithm with byte fidelity: Python <tt>json.dumps</tt>, Go <tt>encoding/json</tt>, and Java Jackson (without explicit configuration) all produce different byte sequences from the same IEEE-754 double in documented cases (round-to-even ties, subnormal values, large-magnitude values requiring scientific notation). Compliance and regulatory contexts (monetary amounts, retention thresholds, anchoring intervals) additionally prefer exact integer or string-encoded decimal representations because float rounding loses the exact bytes that auditors quote. This profile therefore shifts the canonicalization burden off implementers (who would otherwise have to verify ECMA-262 conformance of an underlying JSON library) and onto callers, who are in a better position to choose a portable representation for the use case at hand. A receipt that carries a floating-point number in a digest-covered field is not guaranteed to verify across implementations even when each implementation independently conforms to <xref target="RFC8785"/>, because the conformance burden has not been met by every mainstream JSON library.</t>
      <t>Tool-version-specific semantic equivalence is OUT OF SCOPE for the chain layer of this profile. The chain layer guarantees byte equality only. Examples of semantic equivalence that this profile does not assert and does not require a verifier to assert: SQL keyword case folding (SELECT vs select), filesystem path normalization (trailing slash, redundant separators, symlink resolution), Unicode normalization in any form (NFC, NFD, NFKC, NFKD); Section 3.1 of <xref target="RFC8785"/> requires that all components depending on JCS preserve Unicode string data as-is, and Section 3.2.2.2 of <xref target="RFC8785"/> serializes each code point without normalization, so callers MUST NOT rely on a verifier normalizing strings before comparison, locale-aware string collation (Turkish dotted-i, German sharp-s case folding, ICU collation tables), numeric tolerance (1.0 vs 1, 1e3 vs 1000), or URL percent-encoding choices below the RFC 3986 unreserved set. Higher-level semantic equivalence is a per-tool concern and, where required by a regulator, MUST be expressed in the policy artefact resolved through <tt>policy_digest</tt> (<xref target="policy-digest"/>) rather than in the chain.</t>
      <t>The chain layer of this profile answers a single question for a verifier or a regulator: did the same canonicalized bytes pass through agent X at wall-clock time T, as fixed by the anchor evidence of <xref target="anchoring"/>. Anything beyond that question, including whether two byte sequences are semantically equivalent under a downstream tool, whether a policy update materially changed the meaning of a previously accepted Action, or whether a counterparty's interpretation of the same bytes matched the originator's, is the verifier's concern and is supported by the Audit Pack manifest (<xref target="audit-pack"/>) and the verifier reporting fields of <xref target="reporting"/>, not by the chain itself.</t>
    </section>

    <section anchor="field-profile"><name>Receipt Field Profile</name>
      <t>This section enumerates fields defined by <xref target="ACTA-RECEIPTS"/> and states the additional requirements that this profile places on them. Field names follow <xref target="ACTA-RECEIPTS"/> exactly.</t>
      <t>Compliance Receipts MUST use the upstream wire field name <tt>signature</tt> for the signature object, exactly as defined in Sections 2.1 and 2.1.1 of <xref target="ACTA-RECEIPTS"/>. The keys inside that object are <tt>alg</tt>, <tt>kid</tt>, <tt>sig</tt>. Implementations whose internal storage uses a different field name MUST translate to <tt>signature</tt> on emission and on canonicalization for verification; receipts that appear on the wire under any other top-level field name are non-conformant to <xref target="ACTA-RECEIPTS"/> and to this profile. Anchors MUST be projected into a top-level <tt>anchors</tt> array with a <tt>type</tt> discriminator and a <tt>value</tt> field carrying the anchor bytes (base64-encoded for binary payloads). Flat-column implementations MUST project on emission and Audit Pack export.</t>

      <section anchor="common-fields"><name>Common Payload Fields</name>
        <section anchor="type"><name>type</name>
          <t>Compliance Receipts MUST set <tt>type</tt> to a value drawn from the namespace <tt>protectmcp:decision</tt>, <tt>protectmcp:restraint</tt>, or <tt>protectmcp:lifecycle</tt>, or to an extension namespace registered for use with this profile.</t>
        </section>
        <section anchor="issued-at"><name>issued_at</name>
          <t>REQUIRED upstream and in this profile. The value MUST be an ISO 8601 timestamp with an explicit timezone. The producing system MUST source the value from a clock synchronized to a recognized time authority and MUST NOT backdate the value. Verifiers MUST reject receipts whose <tt>issued_at</tt> is more than 300 seconds ahead of the verifier's own clock. Verifiers MUST NOT reject a receipt solely because <tt>issued_at</tt> lies in the past; past skew is bounded by the applicable retention floor in Sections 5 and 6, not by freshness. Historical receipts within retention MUST verify on the same path as fresh ones.</t>
        </section>
        <section anchor="issuer-id"><name>issuer_id</name>
          <t>REQUIRED upstream and in this profile. The value MUST identify a legal entity, not a natural person. Where the producing system is operated by a Deployer, the <tt>issuer_id</tt> MUST resolve, through the trust anchor metadata in the Audit Pack, to a record naming the Deployer. To preserve the upstream Section 2.2 invariant that <tt>issuer_id</tt> MUST match the <tt>kid</tt> field of the signature object, Compliance Receipts MUST place the same value in both <tt>issuer_id</tt> and <tt>kid</tt>; the verifier resolves that value to a public key through the Audit Pack trust-anchor metadata rather than through the well-known JWK Set endpoint or the RECOMMENDED <tt>sb:issuer:&lt;base58-fingerprint&gt;</tt> form of <xref target="ACTA-RECEIPTS"/> Section 2.1.1. This profile thereby supersedes the upstream RECOMMENDED <tt>kid</tt> format for Compliance Receipts; the upstream RECOMMENDED format remains valid for non-Compliance receipts.</t>
          <t>Implementations SHOULD use a Legal Entity Identifier (LEI) as defined by <xref target="ISO17442"/> where one is allocated to the Deployer. Examples and test fixtures MUST use a placeholder whose four-character LOU prefix (positions 1-4) is not allocated in the GLEIF Local Operating Unit code list, whose positions 5-6 are the ISO 17442 reserved value <tt>00</tt>, and whose two trailing characters (positions 19-20) are the ISO 7064 mod 97-10 check digits computed over positions 1-18 (for example <tt>00000000000000000098</tt>, where the all-zero 18-character base produces the check digits <tt>98</tt> per the ISO 17442-1:2020 Annex A check-digit algorithm, which converts any letters in positions 1-18 to digits A=10 ... Z=35 before the mod 97-10 computation; for an all-zero base the conversion is a no-op); implementations MUST NOT use a real third-party LEI in documentation or test data. Where no LEI is allocated and the Deployer is a US entity, an Employer Identification Number (EIN) issued by the United States Internal Revenue Service or a Central Index Key (CIK) issued by the United States Securities and Exchange Commission MAY be used, expressed as the bare numeric string. Decentralized Identifiers (<xref target="W3C-DID"/>) MAY be used otherwise. Implementations MUST treat the value as opaque on verification; identifier resolution is out of scope for this profile.</t>
          <t><tt>issuer_id</tt> values MUST be bare identifiers without a scheme prefix where the scheme is unambiguous from the value's syntactic form. An LEI is the 20-character alphanumeric string defined by <xref target="ISO17442"/> and is self-identifying through its length and check-digit structure; implementations MUST emit the bare 20-character LEI without a <tt>lei:</tt> or other scheme prefix. EINs and CIKs are likewise emitted as the bare numeric string. Decentralized Identifiers (<xref target="W3C-DID"/>) carry their own scheme prefix (<tt>did:</tt>) as defined by the DID specification and that prefix is intrinsic to the identifier syntax rather than an added scheme tag. The same <tt>kid</tt>-equals-<tt>issuer_id</tt> invariant requires <tt>signature.kid</tt> to be the bare identifier in the same form. The worked example in <xref target="example"/> uses the bare 20-character placeholder LEI <tt>00000000000000000098</tt>; conformant cloud emitters and SDK clients MUST match this form on the wire.</t>
        </section>
        <section anchor="payload-digest"><name>payload_digest (OPTIONAL upstream, REQUIRED in this profile)</name>
          <t>REQUIRED for Compliance Receipts. The value MUST follow the upstream object form (<tt>hash</tt>, <tt>size</tt>, optional <tt>preview</tt>) defined in Section 2.2 of <xref target="ACTA-RECEIPTS"/>; this profile does not redefine the wire shape. The associated payload that this digest covers MUST be retained for the period mandated by the most restrictive applicable regime in Sections 5 and 6 of this document. Implementations MUST NOT discard the underlying payload while a receipt that references it is still within its retention window.</t>
        </section>
        <section anchor="action-ref"><name>action_ref (OPTIONAL upstream, REQUIRED in this profile)</name>
          <t>REQUIRED for Compliance Receipts. The value is a SHA-256 hash of the canonical Action representation as defined in <xref target="ACTA-RECEIPTS"/>. This profile uses <tt>action_ref</tt> as the primary join key for cross-engine reconstruction during an audit.</t>
        </section>
        <section anchor="sandbox-state"><name>sandbox_state (OPTIONAL upstream, REQUIRED for High-Risk in this profile)</name>
          <t>REQUIRED for receipts produced by High-Risk AI Systems under either <xref target="EU-AI-ACT"/> or <xref target="COLORADO-AI-ACT"/>. Upstream defines <tt>sandbox_state</tt> as an OS-level containment status and restricts the value to one of <tt>enabled</tt>, <tt>disabled</tt>, or <tt>unavailable</tt>; this profile inherits that enumeration unchanged. A Deployer that operates a High-Risk AI System and produces a stream of receipts in which <tt>sandbox_state</tt> is consistently disabled SHOULD treat that stream as a finding under the applicable risk-management documentation requirement (Article 9 of <xref target="EU-AI-ACT"/> for the Provider's risk management system, with which a Deployer operating per Article 26(1) is required to be consistent; Section 6-1-1703(2) of the Colorado Revised Statutes) and document the rationale in the Audit Pack metadata.</t>
        </section>
        <section anchor="iteration-id"><name>iteration_id (OPTIONAL upstream, REQUIRED for multi-step in this profile)</name>
          <t>REQUIRED for multi-step agent workflows. The value MUST be stable across all receipts emitted within the same logical task or session so that a regulator can reconstruct the full chain of Actions. <tt>iteration_id</tt> is distinct from the upstream <tt>session_id</tt> field defined in <xref target="ACTA-RECEIPTS"/> Section 3.1.1, which is an opaque MCP session identifier. A Compliance Receipt MAY carry both: <tt>session_id</tt> for MCP-session correlation and <tt>iteration_id</tt> for logical-task correlation.</t>
        </section>
      </section>

      <section anchor="decision-fields"><name>Decision Receipt Fields (type protectmcp:decision)</name>
        <t>The <tt>decision</tt> field value MUST be <tt>allow</tt>, <tt>deny</tt>, <tt>rate_limit</tt>, or <tt>observation</tt>. Implementations using a different internal vocabulary (e.g. <tt>permit</tt> for allow) MUST normalise on emission and on Audit Pack export. The <tt>observation</tt> value records that an Action was observed and the receipt was signed without any policy evaluation having taken place; it is the regulator-honest alternative to emitting <tt>allow</tt> when no policy matched, and MUST NOT appear in a receipt of <tt>type</tt> <tt>protectmcp:decision</tt>. A producing system that has not evaluated a policy for an Action MUST either refuse to issue a Compliance Receipt for that Action or MUST emit the receipt with <tt>type</tt> <tt>protectmcp:lifecycle</tt> and <tt>decision</tt> <tt>observation</tt>; in the latter case the upstream <tt>policy_decision</tt> internal field, if present in the producing system's internal vocabulary, takes the literal value <tt>none</tt>, which the emitter MUST map to <tt>observation</tt> on the wire. Verifiers MUST reject a Compliance Receipt that carries <tt>decision</tt> <tt>observation</tt> together with <tt>type</tt> <tt>protectmcp:decision</tt>; conversely, a Compliance Receipt of <tt>type</tt> <tt>protectmcp:lifecycle</tt> MAY carry <tt>decision</tt> <tt>observation</tt> in addition to the other three vocabulary values. The <tt>policy_digest</tt> requirement of <xref target="policy-digest"/> applies to <tt>observation</tt> receipts in the form of a digest of the producing system's "no policy matched" sentinel policy artefact, which the Deployer MUST retain alongside its other policy artefacts for the applicable retention window.</t>
        <t>The upstream <tt>tool_name</tt> field (REQUIRED in <xref target="ACTA-RECEIPTS"/> Section 3.1.1) is REQUIRED for Compliance Receipts of type <tt>protectmcp:decision</tt>.</t>
        <section anchor="reason"><name>reason (OPTIONAL upstream, REQUIRED for deny/rate_limit in this profile)</name>
          <t>REQUIRED for Compliance Receipts where <tt>decision</tt> is <tt>deny</tt> or <tt>rate_limit</tt>. The value MUST be a machine-readable <tt>reason</tt> code drawn from a vocabulary documented in the Deployer's Audit Pack metadata.</t>
        </section>
        <section anchor="policy-digest"><name>policy_digest (OPTIONAL upstream, REQUIRED in this profile)</name>
          <t>REQUIRED for Compliance Receipts. The value MUST be of the form <tt>sha256:&lt;hex&gt;</tt> and MUST reference a policy artefact that the Deployer retains for the applicable retention window. Verifiers MUST reject Compliance Receipts whose <tt>policy_digest</tt> does not resolve in the Audit Pack.</t>
        </section>
        <section anchor="scanner-decisions"><name>scanner_decisions (OPTIONAL)</name>
          <t>An OPTIONAL <tt>scanner_decisions</tt> field MAY appear in a Compliance Receipt of <tt>type</tt> <tt>protectmcp:decision</tt>. When present, its value MUST be a JSON array of objects, where each object records the outcome of one content scanner plug-in that ran during policy evaluation. Each object has the following members:</t>
          <ul>
            <li><tt>scanner_id</tt> (string, REQUIRED): stable identifier for the scanner plug-in (e.g. <tt>presidio</tt>, <tt>llm-guard</tt>, <tt>cedar</tt>).</li>
            <li><tt>scanner_version</tt> (string, REQUIRED): vendor-reported version string for the scanner instance that produced the outcome.</li>
            <li><tt>scanner_decision</tt> (string, REQUIRED): one of <tt>allow</tt>, <tt>scan_blocked</tt>, or <tt>observation</tt>; matches the wire vocabulary of the parent <tt>decision</tt> field where applicable.</li>
            <li><tt>latency_ms</tt> (integer, OPTIONAL): wall-clock time in milliseconds the scanner took to produce the outcome.</li>
            <li><tt>signature</tt> (string, OPTIONAL): vendor-supplied detached signature over the scanner outcome, used by Deployers that require non-repudiation per scanner instance.</li>
          </ul>
          <t>The field is OPTIONAL because Deployers running a single in-process scanner (the common starter deployment) gain no auditing value from echoing the outcome and would only pay an envelope-size cost. The per-scanner <tt>signature</tt> member is OPTIONAL for the same reason: cryptographic non-repudiation across multiple independent scanner vendors is an Enterprise-tier concern and not mandated by this profile. Verifiers MUST tolerate the absence of <tt>scanner_decisions</tt> and MUST NOT infer that no scanners ran from its absence.</t>
        </section>
      </section>

      <section anchor="hash-chain"><name>Hash-Chain Linkage (OPTIONAL upstream, REQUIRED in this profile)</name>
        <t>Upstream Commitment Mode introduces <tt>previousReceiptHash</tt> as part of an optional extension. This profile makes the linkage REQUIRED. Implementations MUST emit a <tt>previousReceiptHash</tt> field, populated per the digest-scope rule of Section 5.7 of <xref target="ACTA-RECEIPTS"/>: the lowercase hex encoding of SHA-256 over the canonical signing-input bytes of the immediately prior receipt emitted by the same <tt>issuer_id</tt>, where the canonical signing-input bytes are the JCS-canonical serialization (<xref target="RFC8785"/>) of the predecessor's signed payload object (the same bytes the predecessor's cryptographic signature covers), NOT the envelope object that additionally includes the <tt>signature</tt> or <tt>anchors</tt> top-level keys. The first receipt in a chain MUST set this field to the all-zero SHA-256 value (this profile's stipulation; <xref target="ACTA-RECEIPTS"/> Section 5.7 specifies only the digest scope of subsequent links). JSON key is the literal <tt>previousReceiptHash</tt> (camelCase, case-sensitive); snake_case aliases MUST NOT appear on the wire.</t>
        <t>Rationale for the payload-bytes (signing-input) digest scope rather than the envelope-including-signature digest scope: the chain layer's purpose is to make after-the-fact alteration of the predecessor's signed content detectable, and the predecessor's signed content is exactly the bytes its <tt>signature</tt> covers (the canonical payload object). Digesting those bytes binds the chain to what A actually attested to, is recomputable offline from the predecessor's payload alone, and matches Section 5.7 of <xref target="ACTA-RECEIPTS"/>. The chain does not need to bind the predecessor's signature value directly because the predecessor's signature is verified independently under <xref target="mandatory-checks"/>, and cross-agent envelope integrity (where binding the peer's signature value matters) is the role of <tt>counterparty_binding</tt> per <xref target="counterparty-binding"/>, which digests at the envelope-including-signature scope precisely because the peer signature is the load-bearing artefact in the cross-agent case. Implementations that previously digested the envelope-including-signature object MUST migrate to the signing-input scope before emitting chained receipts under this profile; verifiers MUST recompute under the signing-input scope when checking <tt>previousReceiptHash</tt>.</t>
        <t>Each issuer MUST maintain a single linear per-agent chain. When one agent identity emits receipts from multiple concurrent execution paths (for example parallel tool calls dispatched within a single agent loop, or fan-out work performed by a thread pool inside one issuer), the issuer MUST serialize emission through a single predecessor pointer at a time: each newly emitted receipt's <tt>previousReceiptHash</tt> MUST resolve to the SHA-256(JCS(receipt)) of the immediately prior receipt emitted by that same <tt>issuer_id</tt>, taken in emission order, regardless of which concurrent execution path produced it. Parallel sub-chains within one agent identity (for example, a per-receipt <tt>chain_id</tt> discriminator that would partition one issuer's stream into multiple independently advancing chains) are NOT defined by this profile. An issuer that requires parallel sub-chains MUST express each parallel path as a distinct agent identity, with its own <tt>issuer_id</tt> value, its own signing key, and its own per-agent chain rooted at the all-zero SHA-256 genesis value. Rationale: deterministic verification of the chain segment covering an audit window, as required by the regime bindings of Sections 5 and 6 (in particular <xref target="dora-17-2"/>, <xref target="nydfs-500-06"/>, and <xref target="sec-17a-4-f"/>), depends on a single linear total order over the receipts emitted under each agent identity; a verifier reconstructing the chain from a regulator-supplied <tt>issuer_id</tt> needs that ordering to be well-defined without out-of-band metadata.</t>
      </section>

      <section anchor="anchoring"><name>Anchoring (No Upstream Equivalent)</name>
        <t><xref target="ACTA-RECEIPTS"/> lists Sigstore Rekor in its Implementation Status appendix as an OPTIONAL temporal anchor. This profile imposes a normative anchoring requirement.</t>
        <t>Compliance Receipts MUST be anchored. An anchor is an <xref target="RFC3161"/> timestamp token covering the signed envelope, an <xref target="OPENTIMESTAMPS"/> commitment covering the envelope, or both; implementations SHOULD emit both forms. For both anchor types, the bytes committed are SHA-256(JCS(envelope_minus_anchors)), where envelope_minus_anchors is the wire envelope object with the <tt>anchors</tt> top-level key removed prior to canonicalization, leaving the two-key object {<tt>payload</tt>, <tt>signature</tt>}. The <tt>anchors</tt> key MUST be removed from the object, not set to null or to an empty array; these produce different JCS output and break interoperability (mirroring the upstream Section 5.6 stripping rule). The anchor thereby binds payload and signature without being self-referential. The anchor evidence MUST be retained alongside the receipt for the applicable retention window. Verifiers MUST reject Compliance Receipts that lack at least one valid anchor.</t>
        <t>An anchor MAY be attached after issuance if the receipt is persisted with an unambiguous <tt>pending</tt> marker and the anchor lands within a documented bound. For <xref target="OPENTIMESTAMPS"/>, this profile imposes a 7-day deadline; this is a profile-imposed bound, not a property of the OpenTimestamps protocol, whose calendar-to-block upgrade time depends on the calendar operator's publication interval. <xref target="RFC3161"/> tokens MUST be obtained synchronously. A verifier MUST treat a pending receipt as non-conformant once the bound elapses.</t>
        <t>The anchor MAY cover an aggregate of receipts (for example, a Merkle root over a batch) rather than each receipt individually, provided that the inclusion proof linking the receipt to the aggregate is retained alongside the receipt and the aggregate anchor.</t>
        <t>Where the anchor <tt>type</tt> is <xref target="RFC3161"/>, the full TimeStampResp DER bytes MUST be retained, sufficient for offline verification by a holder with access to the TSA's published public key. Time-stamp tokens carrying ESSCertIDv2 per <xref target="RFC5816"/> MUST be accepted by Compliance Verifiers. Where the anchor <tt>type</tt> is <xref target="OPENTIMESTAMPS"/>, the upgrade from the initial calendar attestation to the Bitcoin block attestation MUST be completed within the 7-day profile-imposed bound, and the upgraded proof MUST be retained for the applicable retention window per the second paragraph of this section.</t>
        <t>Each entry in the top-level <tt>anchors</tt> array is an object with the following members.</t>
        <dl>
          <dt><tt>type</tt>:</dt>
          <dd>REQUIRED string discriminator. MUST be one of <tt>rfc3161</tt> or <tt>opentimestamps</tt>.</dd>
          <dt><tt>value</tt>:</dt>
          <dd>REQUIRED on every anchor entry. The anchor token bytes, base64-encoded. For <tt>rfc3161</tt> the value is the base64 encoding of the full TimeStampResp DER bytes (sufficient for offline cryptographic re-verification by a holder with access to the TSA's published public key). For <tt>opentimestamps</tt> the value is the base64 encoding of the OpenTimestamps proof blob (the <tt>.ots</tt> serialization). A verifier MUST cryptographically re-verify the anchor against the signed envelope using these bytes per <xref target="mandatory-checks"/>; anchor entries served without <tt>value</tt> MUST NOT be reported as <tt>anchor_valid_*</tt>=true.</dd>
          <dt><tt>status</tt>:</dt>
          <dd>OPTIONAL informational string. When present, MUST be one of <tt>anchored</tt> (the anchor has reached its final attestation state: an <xref target="RFC3161"/> token has been obtained, or an <xref target="OPENTIMESTAMPS"/> commitment has upgraded to its Bitcoin block attestation), <tt>pending</tt> (the anchor has been requested but the final attestation state has not yet been reached, e.g. an OpenTimestamps commitment that has been submitted to a calendar but has not yet upgraded to a Bitcoin block within the 7-day bound of this section), or <tt>failed</tt> (the anchor submission was attempted and did not produce a usable attestation, e.g. a TSA returned an error response or an OpenTimestamps calendar refused the commitment). <tt>status</tt> is operational metadata; a verifier MUST NOT derive cryptographic validity from <tt>status</tt> alone, and MUST always re-verify the <tt>value</tt> bytes per <xref target="mandatory-checks"/>.</dd>
          <dt><tt>bitcoin_block</tt>:</dt>
          <dd>OPTIONAL informational string. The Bitcoin block hash at which an <xref target="OPENTIMESTAMPS"/> commitment was anchored. Present only on entries with <tt>type</tt>=<tt>opentimestamps</tt> and <tt>status</tt>=<tt>anchored</tt>; absent on <tt>rfc3161</tt> entries and on pending or failed OpenTimestamps entries. <tt>bitcoin_block</tt> is operational metadata; a verifier MUST NOT derive cryptographic validity from <tt>bitcoin_block</tt> alone, and MUST always re-verify the <tt>value</tt> bytes against the OpenTimestamps proof per <xref target="mandatory-checks"/>.</dd>
        </dl>
        <t>An OPTIONAL envelope-level <tt>witness_policy</tt> member, a sibling of <tt>payload</tt>, <tt>signature</tt>, and <tt>anchors</tt>, declares an N-of-M durable-anchoring quorum over the <tt>anchors</tt> array. <tt>witness_policy</tt> is an object with two members: <tt>required</tt>, a REQUIRED integer in the closed range [1, length of <tt>witnesses</tt>]; and <tt>witnesses</tt>, a REQUIRED non-empty JSON array whose values are a subset of the anchor type vocabulary {<tt>rfc3161</tt>, <tt>opentimestamps</tt>}. The <tt>witnesses</tt> array MUST NOT contain duplicate values and MUST NOT contain any value outside that vocabulary; in particular a transparency-log pointer such as Rekor is NOT a witness type and MUST be rejected if it appears in <tt>witnesses</tt>. The policy declares that the receipt's durable anchoring is satisfied only when at least <tt>required</tt> distinct witness types named in <tt>witnesses</tt> each hold a verifiable inclusion proof, that is, an anchor entry of that <tt>type</tt> whose <tt>value</tt> bytes re-verify against SHA-256(JCS(envelope_minus_anchors)) per <xref target="mandatory-checks"/> and, for <tt>opentimestamps</tt>, has upgraded to its Bitcoin block attestation within the 7-day bound of this section.</t>
        <t>A receipt reaches the quorum-met state (the reference implementation reports this as <tt>witness_quorum_met</tt>) only when the count of distinct witness types satisfying the preceding paragraph is greater than or equal to <tt>required</tt>. A Compliance Receipt MUST NOT assert that durable anchoring has been achieved, and a producer MUST NOT set or report <tt>witness_quorum_met</tt>, unless <tt>required</tt> witnesses each hold a real, verifiable inclusion proof; an <tt>anchors</tt> entry with <tt>status</tt>=<tt>pending</tt> or <tt>status</tt>=<tt>failed</tt>, or with absent or non-verifying <tt>value</tt> bytes, does NOT count toward the quorum. This is the same false-attestation principle that governs the rest of this profile: a receipt MUST NOT claim a cryptographic property it cannot prove from retained bytes, and a verifier MUST recompute the quorum from the re-verified <tt>anchors</tt> entries rather than trust any producer-asserted quorum flag. <tt>witness_policy</tt> places no constraint on a receipt that carries no such member; the baseline single-anchor requirement of this section continues to apply to every Compliance Receipt regardless of whether <tt>witness_policy</tt> is present.</t>
      </section>

      <section anchor="extension-fields"><name>Extension Fields</name>
        <t>This profile registers extension fields across five groupings that MAY appear in the signed <tt>payload</tt> object alongside the fields defined by <xref target="ACTA-RECEIPTS"/>: (a) regulatory classification fields (<tt>risk_class</tt>, <tt>incident_class</tt>) defined in this section; (b) the cross-agent envelope-binding field <tt>counterparty_binding</tt> defined in <xref target="counterparty-binding"/>; (c) per-action freshness and integrity fields (<tt>result_digest</tt>, <tt>expires_at</tt>, <tt>nonce</tt>, <tt>tool_fingerprint</tt>, <tt>config_manifest_digest</tt>, <tt>cve_inventory_digest</tt>) and build-provenance fields (<tt>executable_hash</tt>, <tt>sbom_digest</tt>, <tt>slsa_provenance_pointer</tt>, <tt>supply_chain_pointer</tt>) defined in <xref target="result-bound"/> and <xref target="build-provenance"/>; (d) server-built enforcement-attestation fields (<tt>authorized_under_mandate</tt>, <tt>controls_evaluated</tt>) defined in <xref target="enforcement-attestation"/>; and (e) self-declared threat-framework taxonomy fields (<tt>mitre_techniques</tt>, <tt>mitre_atlas</tt>, <tt>owasp_llm_top10</tt>, <tt>nist_ai_rmf</tt>, <tt>iso_42001</tt>, <tt>eu_ai_act_articles</tt>), the opaque caller-supplied <tt>rfc3161_timestamp</tt> token, and the platform-set guard <tt>framework_mappings_self_declared</tt> defined in <xref target="threat-framework"/>. All extension fields appear inside the signed <tt>payload</tt> object and are therefore covered by the upstream Section 5.6 signature scope.</t>
        <dl>
          <dt><tt>risk_class</tt>:</dt>
          <dd>A vocabulary term identifying the risk classification of the Action under the Deployer's risk management documentation. The vocabulary MUST be referenced in the Audit Pack metadata. Where the Deployer operates under <xref target="EU-AI-ACT"/>, the documentation is the Provider's Article 9 risk management system as referenced via the instructions for use under Article 26(1); where the Deployer operates under <xref target="COLORADO-AI-ACT"/>, the documentation is the Section 6-1-1703(2) risk management policy and program.</dd>
          <dt><tt>incident_class</tt>:</dt>
          <dd>A vocabulary term identifying the incident classification of the Action under the applicable regime: an ICT-related incident under <xref target="DORA"/>, with classification criteria in <xref target="REG-2024-1772"/> and the canonical reporting enumeration of Annex II data glossary, field 3.23 (Type of the incident) of <xref target="REG-2025-302"/> (verifiers MUST resolve the canonical values from the regulation directly); a Cybersecurity Event under 23 NYCRR 500.1(f) (or, where the Section 500.17(a) reporting threshold is met, a Cybersecurity Incident under 23 NYCRR 500.1(g)) for Covered Entities of <xref target="NYDFS-500"/>; a Covered Cyber Incident under <xref target="CIRCIA"/> once the final rule takes effect; or a security incident under 45 CFR 164.304 for Covered Entities of <xref target="HIPAA-SECURITY"/>. Implementations MAY refine the set, provided the flattened mapping in the Audit Pack manifest (<xref target="audit-pack"/>) projects each refinement to the applicable canonical category for each in-scope regime.</dd>
        </dl>
        <t><tt>risk_class</tt> MUST be encoded as a JSON string. <tt>incident_class</tt> MUST be encoded as a JSON string drawn from the canonical vocabulary referenced in the Audit Pack, OR as a JSON array of such strings to preserve cross-regime classification (for example, a single Action that is both a DORA ICT-related incident and a CIRCIA Covered Cyber Incident, or both a NYDFS Cybersecurity Incident and a CIRCIA Covered Cyber Incident). Both fields are OPTIONAL at the syntactic level but MAY be REQUIRED by the regime bindings in Sections 5 and 6 of this document.</t>
        <t>Implementations MAY define additional extension fields. Such fields MUST NOT collide with names defined by <xref target="ACTA-RECEIPTS"/> or by this document. Implementations defining extension fields SHOULD register them in the registry described in <xref target="iana"/>.</t>
      </section>

      <section anchor="counterparty-binding"><name>Counterparty Binding</name>
        <t>This section is normative. <tt>counterparty_binding</tt> is an in-payload object an acknowledging agent ("B") emits to carry a cryptographic digest of the full signed envelope of an originating agent ("A"). It provides cross-agent byte-equality evidence when a shared intermediary sits between two honest agents and the per-agent hash chains of <xref target="hash-chain"/> validate independently regardless of whether B's observed bytes equal A's signed bytes. <tt>action_ref</tt> is a correlation anchor, not a cryptographic binding (<xref target="ACTA-RECEIPTS"/> Section 2.2); <tt>counterparty_binding</tt> moves the evidence onto B's own COSE or JWS signature, which the verifier already trusts.</t>
        <section anchor="counterparty-binding-wire"><name>Wire Shape</name>
          <t>The field MUST appear inside the signed <tt>payload</tt> object. It MUST NOT appear in unprotected COSE or JWS header parameters, or in <tt>external_aad</tt> per <xref target="RFC9052"/> Section 4.3 when the receipt is used for audit (<tt>external_aad</tt> is permissible only in transport-optimized modes out of scope for Compliance Receipts). For COSE-framed receipts the field sits inside the COSE_Sign1 or COSE_Sign payload per <xref target="RFC9052"/> Section 4.1; for JWS-framed receipts it is a top-level claim per <xref target="RFC7515"/>.</t>
          <t>The field is an object with the following members.</t>
          <dl>
            <dt><tt>envelope_hash</tt>:</dt>
            <dd>
              <t>REQUIRED string. Base64-encoded SHA-256 digest computed over A's entire serialized signed envelope, including A's signature bytes. The digest input is framing-specific:</t>
              <ul>
                <li>JSON-framed (this profile's default for receipts not transported under COSE or JWS, and mandatory-to-implement for any conformant Compliance Receipt implementation): the JCS-canonical UTF-8 byte sequence of A's signed envelope JSON object per <xref target="RFC8785"/>, where the envelope is the three-key object <tt>{"payload": &lt;signed payload object&gt;, "signature": &lt;signature object with alg, kid, sig members&gt;, "anchors": &lt;array of anchor objects, OPTIONAL&gt;}</tt>. The <tt>payload</tt> object carries the signed fields A emitted (including <tt>type</tt>, <tt>issuer_id</tt>, <tt>issued_at</tt>, <tt>action_ref</tt>, <tt>payload_digest</tt>, <tt>previousReceiptHash</tt>, <tt>decision</tt>, and any extension fields under <xref target="extension-fields"/>); the <tt>signature</tt> object carries the algorithm identifier, key identifier, and base64- or base64url-encoded signature bytes exactly as A emitted them. B MUST NOT re-canonicalize A's payload or strip the <tt>anchors</tt> array before computing the digest.</li>
                <li>COSE-framed: the full COSE_Sign1 or COSE_Sign byte string per <xref target="RFC8949"/> Section 4.2 (deterministic encoding).</li>
                <li>JWS-framed: the full JWS Compact Serialization (header.payload.signature) after payload canonicalization per <xref target="RFC8785"/>.</li>
              </ul>
              <t>The digest algorithm is SHA-256 (mandatory-to-implement). The encoding MUST be standard base64 per <xref target="RFC4648"/> Section 4 on emission, OR base64url per Section 5 where the surrounding transport requires URL-safe encoding; verifiers MUST accept both alphabets and MUST normalise to a single alphabet (typically standard base64) before byte-comparing to a recomputed value. Including A's signature in the digest scope binds the signed-over content of A's receipt at the envelope level and prevents an intermediary that re-signs A's claims with a different key from escaping detection.</t>
              <t>The framing in which A's envelope was emitted MUST be preserved through B's binding. The value of <tt>envelope_hash</tt> is framing-specific because JCS-canonical JSON (UTF-16 code-unit lexicographic key ordering per <xref target="RFC8785"/>), COSE deterministic encoding (length-then-byte map-key ordering per <xref target="RFC8949"/> Section 4.2), and JWS Compact Serialization with JCS-canonical payload (UTF-16 code-unit lexicographic ordering per <xref target="RFC8785"/>) produce different byte sequences from the same semantic payload-and-signature, and the three framings therefore yield different <tt>envelope_hash</tt> values for the same underlying receipt. A transcoding intermediary that re-frames A's envelope (JSON to COSE, COSE to JWS, or any other pairing) changes the digest input and MUST be treated as a tampering event by the verifier; verifiers MUST NOT reframe an envelope before recomputing <tt>envelope_hash</tt>.</t>
              <t>Future revisions MAY extend to additional digest algorithms drawn from the <xref target="ACTA-RECEIPTS"/> digest algorithm registry; implementations that require algorithm negotiation SHOULD carry the algorithm identifier out of band in the Audit Pack manifest rather than in the wire field.</t>
            </dd>
            <dt><tt>receipt_ref</tt>:</dt>
            <dd>REQUIRED opaque content-addressed locator the verifier resolves through the Audit Pack or a Deployer-published index to A's full signed envelope. The value is an opaque string from the verifier's perspective; producers MAY use any stable identifier scheme (URI, content-addressed digest, opaque database id) so long as the Audit Pack resolution layer returns the correct envelope bytes. Future profiles (for example, a SCITT-style inclusion-proof profile under <xref target="ACTA-RECEIPTS"/> Section 4.2 extension semantics) MAY layer on this field.</dd>
            <dt><tt>expect_ack_from</tt>:</dt>
            <dd>OPTIONAL string. The expected acknowledging-party identifier, expressed as a <tt>kid</tt> or <tt>issuer_id</tt> value matching the same bare-identifier form required by <xref target="issuer-id"/>. When present, the field declares which acknowledging party A or the producer expects to sign over this receipt's bytes; a verifier MAY use <tt>expect_ack_from</tt> to cross-check that the acknowledging receipt's <tt>kid</tt> matches the expected identifier. Verifiers MUST NOT reject solely on absence of an acknowledging receipt; absence is a liveness-loss signal observable through Audit Pack metadata rather than a non-conformance condition on the current receipt.</dd>
            <dt><tt>transport_label</tt>:</dt>
            <dd>OPTIONAL string (<tt>mcp</tt>, <tt>bus</tt>, <tt>orchestrator</tt>, <tt>http</tt>). Operational only; verifiers MUST NOT derive trust from this label.</dd>
          </dl>
          <sourcecode type="json"><![CDATA[
"counterparty_binding": {
  "envelope_hash": "bDqg...5PE=",
  "receipt_ref": "asqav-receipt://org/123/agent_A/seq/4811",
  "expect_ack_from": "00000000000000000098",
  "transport_label": "mcp"
}
]]></sourcecode>
          <t>The COSE form follows the same member set under deterministic CBOR map ordering per <xref target="RFC8949"/> Section 4.2.</t>
        </section>
        <section anchor="counterparty-binding-emitter"><name>Emitter Behaviour</name>
          <t>B SHOULD emit <tt>counterparty_binding</tt> when any of the following hold: A's signing request flagged the action as requiring acknowledgment (for example, by populating an <tt>expect_ack_from</tt> list); the Deployer's risk management documentation requires bilateral byte-binding; or B is operating under the guidance of <xref target="trust-boundary"/>. B MUST compute <tt>envelope_hash</tt> over the exact byte stream it received and accepted, not over a re-canonicalization at B; re-canonicalizing at B masks intermediary tampering whenever the tampered bytes canonicalize to the same payload object, which is the threat case this section addresses. Where one acknowledgment receipt confirms envelopes from N originators, the field MAY be an array of objects; pairwise bindings cannot prove all N originators emitted identical bytes (see <xref target="issuer-misrep"/>).</t>
        </section>
        <section anchor="counterparty-binding-verifier"><name>Verifier Behaviour</name>
          <t>A Compliance Verifier processing a receipt carrying <tt>counterparty_binding</tt> MUST, in addition to <xref target="mandatory-checks"/>, resolve <tt>receipt_ref</tt> through the Audit Pack or a Deployer-published index to A's full signed envelope, recompute the SHA-256 digest of that envelope under the scope rule of <xref target="counterparty-binding-wire"/>, base64-encode the result, and compare to <tt>envelope_hash</tt>. A non-resolving <tt>receipt_ref</tt> or a digest mismatch MUST cause the acknowledging receipt to be reported non-conformant; liveness loss at A MUST NOT be silently treated as success. Where <tt>expect_ack_from</tt> is present, the verifier SHOULD additionally check that the acknowledging receipt's <tt>signature.kid</tt> matches the declared identifier (under the bare-identifier form required by <xref target="issuer-id"/>); mismatch SHOULD be reported as an axis flag rather than as outright non-conformance because the field is OPTIONAL.</t>
          <t>The Deployer or Audit Pack producer MUST retain A's signed envelope for at least as long as any acknowledging receipt binding it remains within retention under Sections 5 and 6. For chains of three or more agents, this profile defaults to pairwise bindings; multi-signer co-presence under <xref target="RFC9052"/> Section 4.1 is OPTIONAL, and verifiers MUST NOT treat a co-signed envelope as a substitute for a pairwise binding chain.</t>
        </section>
      </section>

      <section anchor="result-bound"><name>Result-Bound and Freshness Extensions</name>
        <t>This section is normative. It defines six OPTIONAL extension fields that may appear inside the signed <tt>payload</tt> object to bind the receipt to the byte-equality of a downstream result, to bound the freshness of a decision, to declare the tool and configuration that produced the action, and to record the supply-chain Common Vulnerabilities and Exposures (CVE) inventory in effect at signing time. The fields are independently OPTIONAL; an implementation MAY emit any subset. All six are covered by the upstream Section 5.6 signature scope under <xref target="ACTA-RECEIPTS"/>.</t>
        <dl>
          <dt><tt>result_digest</tt>:</dt>
          <dd>OPTIONAL object of the same shape as <tt>payload_digest</tt> defined in Section 2.2 of <xref target="ACTA-RECEIPTS"/>: REQUIRED string <tt>hash</tt> formatted <tt>sha256:&lt;64 lowercase hex chars&gt;</tt>, REQUIRED integer <tt>size</tt> in bytes, OPTIONAL string <tt>preview</tt>. The digest covers the canonicalized bytes of the downstream Action's result body (response payload, tool output, model completion). The field is emitted on a follow-up <tt>protectmcp:observation:result_bound</tt> receipt that references the originating <tt>protectmcp:decision</tt> via <tt>action_ref</tt>; a verifier processing a result-bound observation MUST treat a digest mismatch between <tt>result_digest</tt> and the verifier's local recomputation over retained result bytes as a non-conformance condition. Result bytes covered by <tt>result_digest</tt> are subject to the same retention floor as the originating decision receipt under Sections 5 and 6.</dd>
          <dt><tt>expires_at</tt>:</dt>
          <dd>OPTIONAL ISO 8601 timestamp with explicit timezone, encoded as a JSON string. Declares the wall-clock time after which the producing system considers the decision result stale and not safe to replay. The field provides an upper freshness bound that is additive to the 300-second forward-skew bound on <tt>issued_at</tt> of <xref target="issued-at"/>; <tt>expires_at</tt> bounds replay safety from above, the forward-skew rule bounds emission honesty from above. A verifier MUST reject a downstream action that replays a decision whose <tt>expires_at</tt> lies in the past relative to the replay's wall clock; verifiers MUST NOT reject the originating receipt itself solely because <tt>expires_at</tt> has elapsed (the receipt remains valid as a record of the decision at <tt>issued_at</tt>).</dd>
          <dt><tt>nonce</tt>:</dt>
          <dd>OPTIONAL JSON string carrying a producer-generated value that is unique across the producer's emission stream for the lifetime of the cryptographic key identified by <tt>kid</tt>. The field SHOULD be a base64url-encoded random value of at least 16 bytes, OR a structured identifier (UUIDv4, UUIDv7, ULID) the producer guarantees globally unique. Verifiers SHOULD reject a second receipt that carries the same <tt>nonce</tt> under the same <tt>issuer_id</tt> as a replay candidate; the rejection is informational where the bound action is idempotent and load-bearing where the bound action is not. The field is OPTIONAL at the syntactic level but is a SHOULD-emit for any producer whose downstream actions are not idempotent.</dd>
          <dt><tt>tool_fingerprint</tt>:</dt>
          <dd>OPTIONAL JSON string formatted <tt>sha256:&lt;64 lowercase hex chars&gt;</tt> over the canonical declaration of the tool that produced the Action, including the tool's name, version, declared input schema, declared output schema, and any tool-specific configuration the producer treats as part of the tool's identity. The canonicalization rule for the declaration MUST be JCS per <xref target="RFC8785"/>. The field binds a receipt to a specific tool identity; a verifier or auditor reproducing the Action can detect tool drift (the same tool name with a different version, schema, or configuration) by comparing fingerprints across receipts in the same chain. The field is OPTIONAL and complementary to <tt>action_ref</tt>: <tt>action_ref</tt> identifies the call, <tt>tool_fingerprint</tt> identifies the callee.</dd>
          <dt><tt>config_manifest_digest</tt>:</dt>
          <dd>OPTIONAL JSON string formatted <tt>sha256:&lt;64 lowercase hex chars&gt;</tt> over the canonical bytes of the producer's configuration manifest in effect at the time the Action was signed. The manifest content is operator-defined and SHOULD include the producer's policy bundle reference, model identifiers and versions, prompt template digests, retrieval index identifiers, and any other inputs whose change would constitute a substantial modification of the producing system under Article 43 of <xref target="EU-AI-ACT"/> or under Section 6-1-1701 of <xref target="COLORADO-AI-ACT"/>. The field is OPTIONAL but, when emitted, SHOULD resolve through the Audit Pack to retained manifest bytes for the duration of the longest applicable retention floor in Sections 5 and 6.</dd>
          <dt><tt>cve_inventory_digest</tt>:</dt>
          <dd>OPTIONAL JSON string formatted <tt>sha256:&lt;64 lowercase hex chars&gt;</tt> over the canonical bytes of the producer's CVE inventory at the time the Action was signed. The inventory content SHOULD list the CVE identifiers known to apply to the producer's executing image and its declared runtime dependencies, plus the producer's accepted-residual rationale per <xref target="EU-AI-ACT"/> Article 15 robustness obligations or the equivalent obligations under Sections 5 and 6. The field binds a snapshot of the producer's known-vulnerability surface to the receipt; a regulator examining the receipt can resolve the digest through the Audit Pack to the canonical inventory bytes that were in effect when the Action was signed, rather than relying on a later-time inventory that may have been updated after the Action was performed.</dd>
        </dl>
        <t>Implementations emitting <tt>result_digest</tt> SHOULD use the dedicated <tt>protectmcp:observation:result_bound</tt> type registered in <xref target="iana-type-namespaces"/> for the follow-up receipt that carries the bound digest. Implementations MAY emit <tt>expires_at</tt>, <tt>nonce</tt>, <tt>tool_fingerprint</tt>, <tt>config_manifest_digest</tt>, and <tt>cve_inventory_digest</tt> on any receipt type defined by this profile; the fields are type-agnostic.</t>
      </section>

      <section anchor="build-provenance"><name>Build-Provenance Extensions</name>
        <t>This section is normative. It defines four OPTIONAL extension fields that bind the receipt to the supply-chain provenance of the executable that produced the Action. The four fields form a layered subsumption set: <tt>executable_hash</tt> binds the running binary, <tt>sbom_digest</tt> binds the dependency manifest the binary was built from, <tt>slsa_provenance_pointer</tt> resolves to the SLSA attestation envelope for that build, and <tt>supply_chain_pointer</tt> resolves to a transparency-log entry (in-toto, Sigstore, or Rekor) covering the build. An implementation MAY emit any subset. All four are covered by the upstream Section 5.6 signature scope under <xref target="ACTA-RECEIPTS"/>.</t>
        <dl>
          <dt><tt>executable_hash</tt>:</dt>
          <dd>OPTIONAL JSON string formatted <tt>sha256:&lt;64 lowercase hex chars&gt;</tt> over the canonical bytes of the executable that invoked the Action. For container-based producers the canonical bytes are the immutable image manifest digest of the running image (the value an OCI registry returns under the same name plus tag, computed under the OCI Image Manifest Specification). For non-container executables the canonical bytes are the SHA-256 of the on-disk binary file at the path the producer's runtime resolved. The field binds build-side provenance into the signed receipt: a regulator examining the receipt can recover the exact executable identity that produced the Action without trusting any side-channel attestation. A verifier MAY cross-check <tt>executable_hash</tt> against the executable identity declared in the SLSA attestation resolved through <tt>slsa_provenance_pointer</tt>; mismatch SHOULD be reported as an axis flag rather than as non-conformance because the two fields may identify the same artefact under different addressing schemes.</dd>
          <dt><tt>sbom_digest</tt>:</dt>
          <dd>OPTIONAL JSON string formatted <tt>sha256:&lt;64 lowercase hex chars&gt;</tt> over the canonical bytes of the Software Bill of Materials (SBOM) document covering the executing image. The canonical form MUST be either CycloneDX (any 1.x specification version, JSON form, with the canonicalization rule defined by CycloneDX itself) or SPDX (version 2.x or later, JSON form, with the canonicalization rule defined by SPDX itself); the producer SHOULD record the chosen format and version in the Audit Pack manifest entry for the receipt so a verifier can recompute the digest. The field complements <tt>executable_hash</tt>: <tt>executable_hash</tt> identifies the artefact, <tt>sbom_digest</tt> identifies the dependency closure of that artefact.</dd>
          <dt><tt>slsa_provenance_pointer</tt>:</dt>
          <dd>OPTIONAL JSON string carrying an https URL that resolves to the Supply-chain Levels for Software Artifacts (SLSA) provenance attestation envelope for the build that produced the executable identified by <tt>executable_hash</tt>. The pointer target SHOULD be the SLSA Provenance v1.0 in-toto statement form; producers MAY emit earlier SLSA versions where toolchain support is incomplete, and verifiers SHOULD accept any SLSA version they implement. The field shifts the trust root for build-side provenance off the producer's self-attestation and onto the build platform's attestation; the verifier's confidence in the resolved attestation is bounded by the verifier's trust in the build platform's signing root.</dd>
          <dt><tt>supply_chain_pointer</tt>:</dt>
          <dd>OPTIONAL JSON string carrying an https URL that resolves to a transparency-log entry covering the build that produced the executable identified by <tt>executable_hash</tt>. The pointer target SHOULD be an in-toto attestation, a Sigstore entry, or a Rekor entry, in that preference order where the producer can choose; verifiers SHOULD accept any of the three. The field provides a transparency-log-backed audit path for the build, independent of the SLSA attestation envelope referenced by <tt>slsa_provenance_pointer</tt>; the two fields are complementary because a transparency-log entry attests inclusion under a public log, while a SLSA attestation attests build-platform output bytes.</dd>
        </dl>
        <t>The four fields are type-agnostic and MAY appear on any receipt type defined by this profile. Where a Deployer operates under a regulatory regime that requires build-side traceability (Article 12 of <xref target="EU-AI-ACT"/> read together with Article 17 of <xref target="DORA"/>; the audit-controls obligation of 45 CFR 164.312(b) of <xref target="HIPAA-SECURITY"/>; the recordkeeping rule of <xref target="SEC-17A-4"/> read with <xref target="NYDFS-500"/> 23 NYCRR 500.6), the Deployer SHOULD emit at least <tt>executable_hash</tt> on every <tt>protectmcp:decision</tt> receipt and SHOULD retain the SBOM, the SLSA attestation, and the transparency-log entry through the longest applicable retention floor in Sections 5 and 6.</t>
      </section>

      <section anchor="enforcement-attestation"><name>Enforcement-Attestation Extensions</name>
        <t>This section is normative. It defines two OPTIONAL extension fields that record, inside the signed <tt>payload</tt> object, which authorization and enforcement controls the issuing platform genuinely evaluated when it signed the receipt. Both fields are server-built: they are populated by the issuing platform at signing time, never carried in the producer's signing request, and a caller-supplied value for either field MUST be dropped by the issuing platform before signing. Both fields are covered by the upstream Section 5.6 signature scope under <xref target="ACTA-RECEIPTS"/>. The design rule for both fields is omission-over-false attestation: a control that did not run is represented by the absence of its key, never by a present key asserting a result the control did not produce. The two fields each carry a false-attestation guard that rejects a present-but-malformed attestation, in the same spirit as the <tt>framework_mappings_self_declared</tt> guard of <xref target="extension-fields"/> and the <tt>witness_policy</tt> quorum guard of <xref target="anchoring"/>.</t>
        <dl>
          <dt><tt>authorized_under_mandate</tt>:</dt>
          <dd>OPTIONAL object recording that the Action was signed under a self-declared authorizing mandate. The object carries four members: <tt>mandate_id</tt> (REQUIRED string, the issuer-scoped identifier of the mandate the Action was authorized under), <tt>issuer_id</tt> (REQUIRED string, the identifier of the party that issued the mandate, in the bare-identifier form required by <xref target="issuer-id"/>), <tt>scope_digest</tt> (REQUIRED string formatted <tt>sha256:&lt;64 lowercase hex chars&gt;</tt> over the canonical bytes of the mandate's authorized-action-types scope), and <tt>verified</tt> (REQUIRED boolean). The trust semantics are deliberately narrow: <tt>verified</tt>=<tt>true</tt> asserts self-declared issuer authority, the same trust level as <tt>framework_mappings_self_declared</tt> of <xref target="extension-fields"/>, and is NEVER an issuing-platform attestation of verified third-party authorization. The mandate binding is self-declared by the issuer, is evaluated against the issuing platform's own clock at signing time, and scopes the Action to a set of authorized action types; this profile does NOT define a value cap, a counterparty restriction, or any other constraint on the mandate, and a verifier MUST NOT infer one from the presence of this field. A verifier resolves <tt>scope_digest</tt> by retrieving the mandate identified by <tt>mandate_id</tt> through the Audit Pack or a Deployer-published mandate index and recomputing the digest over the canonical scope bytes; a mismatch MUST be reported as a non-conformance condition. The false-attestation guard for this field rejects an <tt>authorized_under_mandate</tt> object that is present but does not carry all of <tt>mandate_id</tt>, <tt>issuer_id</tt>, <tt>verified</tt>=<tt>true</tt>, and a well-formed <tt>scope_digest</tt>: a present-but-malformed attestation is rejected at signing time rather than signed and surfaced as truth.</dd>
          <dt><tt>controls_evaluated</tt>:</dt>
          <dd>OPTIONAL object enumerating the enforcement controls that genuinely fired when the issuing platform signed the Action, plus the allow result. The member keys are drawn from a closed set: <tt>emergency_halt</tt>, <tt>delegation_scope</tt>, <tt>quorum</tt>, <tt>mandate</tt>, <tt>policy</tt>, <tt>content_scan</tt>, and <tt>result</tt>; an unknown key MUST be rejected. Each control key is present ONLY when its control actually ran on this sign; an absent key means the control never ran on this sign, and a verifier MUST NOT infer from an absent key that the control ran and passed silently. The <tt>quorum</tt> member, when present, MUST carry <tt>fired</tt>=<tt>true</tt> together with a 64-lowercase-hex <tt>attestation_hash</tt> proving the quorum evaluation; the <tt>policy</tt> member, when present and asserting a policy was evaluated, MUST carry <tt>matched_count</tt> greater than or equal to 1. The false-attestation guard for this field rejects a present-but-malformed <tt>controls_evaluated</tt> object: an unknown control key, a <tt>quorum</tt> member lacking <tt>fired</tt>=<tt>true</tt> plus a 64-hex <tt>attestation_hash</tt>, or a <tt>policy</tt> member asserting evaluation without <tt>matched_count</tt> greater than or equal to 1, is rejected at signing time. Because the field is server-built and a caller-supplied <tt>controls_evaluated</tt> is dropped before signing, a verifier MAY treat the enumerated keys as the issuing platform's own record of which controls it ran.</dd>
        </dl>
        <t>Both fields are type-agnostic and MAY appear on any receipt type defined by this profile, though they are most commonly emitted on <tt>protectmcp:decision</tt> receipts where an authorization or enforcement evaluation produced the recorded decision. Neither field replaces the policy-evaluation honesty rule that an issuing platform MUST NOT assert a control ran when it did not (the design note carried under <xref target="security"/>): <tt>controls_evaluated</tt> records which controls ran, not that any control blocked, and an absent control key is the conformant representation of a control that did not run.</t>
      </section>

      <section anchor="threat-framework"><name>Threat-Framework Taxonomy Extensions</name>
        <t>This section is normative. It defines six OPTIONAL caller-supplied taxonomy fields, one OPTIONAL caller-supplied opaque timestamp token, and one platform-set false-attestation guard boolean, all of which MAY appear inside the signed <tt>payload</tt> object. The six taxonomy fields record producer-asserted mappings of the Action into established threat-and-control catalogues; they are self-declared and are NOT verified by the issuing platform. The guard boolean exists so that a verifier can tell a self-declared classification apart from a platform-verified one. All eight fields are covered by the upstream Section 5.6 signature scope under <xref target="ACTA-RECEIPTS"/>, and an implementation MAY emit any subset.</t>
        <dl>
          <dt><tt>mitre_techniques</tt>:</dt>
          <dd>OPTIONAL JSON array of MITRE ATT&amp;CK technique identifiers (for example <tt>T1059</tt>, <tt>T1078</tt>) self-declared by the producer. The values are referenced by identifier from the MITRE ATT&amp;CK enterprise matrix. The field is not verifier-checked by the issuing platform; when the array is populated the issuing platform MUST set <tt>framework_mappings_self_declared</tt> to <tt>true</tt>.</dd>
          <dt><tt>mitre_atlas</tt>:</dt>
          <dd>OPTIONAL JSON array of MITRE ATLAS identifiers (for example <tt>AML.T0051</tt>) covering AI-system-specific adversary techniques, self-declared by the producer and referenced by identifier from the MITRE ATLAS catalogue. When populated the issuing platform MUST set <tt>framework_mappings_self_declared</tt> to <tt>true</tt>.</dd>
          <dt><tt>owasp_llm_top10</tt>:</dt>
          <dd>OPTIONAL JSON array of OWASP Top 10 for LLM Applications identifiers (for example <tt>LLM01</tt>, <tt>LLM02</tt>), self-declared by the producer and referenced by identifier from the OWASP Top 10 for LLM Applications publication. When populated the issuing platform MUST set <tt>framework_mappings_self_declared</tt> to <tt>true</tt>.</dd>
          <dt><tt>nist_ai_rmf</tt>:</dt>
          <dd>OPTIONAL JSON array of NIST AI Risk Management Framework function identifiers and subcategories (for example <tt>GOVERN-1.1</tt>, <tt>MEASURE-2.7</tt>), self-declared by the producer and referenced from <xref target="NIST-AI-RMF"/>. When populated the issuing platform MUST set <tt>framework_mappings_self_declared</tt> to <tt>true</tt>.</dd>
          <dt><tt>iso_42001</tt>:</dt>
          <dd>OPTIONAL JSON array of ISO/IEC 42001:2023 control identifiers (for example <tt>A.6.2.6</tt>), self-declared by the producer and referenced from ISO/IEC 42001:2023. When populated the issuing platform MUST set <tt>framework_mappings_self_declared</tt> to <tt>true</tt>.</dd>
          <dt><tt>eu_ai_act_articles</tt>:</dt>
          <dd>OPTIONAL JSON array of EU AI Act article identifiers (for example <tt>Article-12</tt>, <tt>Article-15</tt>), self-declared by the producer and referenced from <xref target="EU-AI-ACT"/>. When populated the issuing platform MUST set <tt>framework_mappings_self_declared</tt> to <tt>true</tt>.</dd>
          <dt><tt>rfc3161_timestamp</tt>:</dt>
          <dd>OPTIONAL JSON string carrying a base64-encoded <xref target="RFC3161"/> TimeStampResp (DER) supplied by the producer at signing time and preserved verbatim on the receipt for offline TSA chain verification independent of any platform-issued anchors. The payload entry is an opaque caller-supplied token, NOT the per-receipt anchor produced by the platform under <xref target="anchoring"/>; the base64 encoding is per <xref target="RFC4648"/>. This field does not flip <tt>framework_mappings_self_declared</tt>.</dd>
          <dt><tt>framework_mappings_self_declared</tt>:</dt>
          <dd>OPTIONAL JSON boolean false-attestation guard set by the issuing platform. The platform MUST set it to <tt>true</tt> whenever any of <tt>mitre_techniques</tt>, <tt>mitre_atlas</tt>, <tt>owasp_llm_top10</tt>, <tt>nist_ai_rmf</tt>, <tt>iso_42001</tt>, or <tt>eu_ai_act_articles</tt> is populated. A producer-supplied value of <tt>false</tt> alongside a populated taxonomy field MUST be overridden by the issuing platform, in the same spirit as the false-attestation guards of <xref target="enforcement-attestation"/> and the <tt>witness_policy</tt> quorum guard of <xref target="anchoring"/>. The guard does not assert that the self-declared mappings are correct; it asserts only that they are self-declared rather than platform-verified, and a verifier MUST NOT treat a populated taxonomy field as platform-verified.</dd>
        </dl>
        <t>The eight fields are type-agnostic and MAY appear on any receipt type defined by this profile.</t>
      </section>
    </section>

    <section anchor="eu-bindings"><name>European Union Bindings</name>
      <section anchor="article-12"><name>EU AI Act Article 12 Binding</name>
        <t>Each subsection cites the operative phrase of Article 12 and binds it to the receipt field that satisfies it.</t>
        <section anchor="art12-1"><name>Article 12(1), automatic recording of events</name>
          <t>Article 12(1) requires High-Risk AI Systems to technically allow for the automatic recording of events (logs) over the lifetime of the system. The signed-receipt format provides one mechanism that satisfies that logging capability; alternative mechanisms remain valid. Where this profile is chosen, a Compliance Receipt SHOULD be produced for every Action against an external resource, and a configuration change that disables receipt generation SHOULD be recorded as a protectmcp:lifecycle Compliance Receipt. Implementations MAY emit at finer or coarser granularity so long as the log set, taken together, satisfies Article 12(2)(a) through (c).</t>
        </section>
        <section anchor="art12-2a"><name>Article 12(2)(a), identifying situations that may result in the high-risk AI system presenting a risk within the meaning of Article 79(1) or in a substantial modification</name>
          <t>The combination of <tt>type</tt>, <tt>decision</tt>, <tt>reason</tt>, and <tt>policy_digest</tt> MUST be sufficient for an auditor to identify, by query alone, receipts that correspond to risk situations enumerated in the Deployer's risk management documentation. Where the Deployer classifies an Action as risk-bearing, the receipt MUST carry a <tt>risk_class</tt> extension field.</t>
        </section>
        <section anchor="art12-2b"><name>Article 12(2)(b), facilitating the post-market monitoring referred to in Article 72</name>
          <t>The hash-chain linkage required by <xref target="hash-chain"/> satisfies post-market monitoring traceability. The chain head MUST be made available to the Provider and to the competent authority on request.</t>
        </section>
        <section anchor="art12-2c"><name>Article 12(2)(c), monitoring the operation of high-risk AI systems referred to in Article 26(5)</name>
          <t>Any change to the policy artefact referenced by <tt>policy_digest</tt> MUST produce a new digest. A change in <tt>policy_digest</tt> between two otherwise-comparable Actions may be examined by the Deployer or by a regulator as a candidate substantial-modification event under Article 43, and MUST be retained at least as long as the longest receipt in the chain that references either digest.</t>
        </section>
        <section anchor="art12-retention"><name>Retention</name>
          <t>Article 12 itself sets no retention period; the operative deployer floor is Article 26(6) ("at least six months"). The parallel provider floor in Article 19(1) sets the same six-month minimum on Providers; this profile's retention bindings are written from the Deployer perspective, and a Provider that wishes to use Compliance Receipts as its Article 19(1) record SHOULD adopt the Deployer floor explicitly through a separate Provider-role binding (deferred to a future revision).</t>
          <t>EU AI Act Article 26(6) requires six months of logs (interpreted as 184 days when expressed as a day-count floor for hash-chain anchoring intervals). The normative requirement on Compliance Receipts is: implementations MUST retain receipts until the later of (a) the day six calendar months after the date of the Action, computed calendar-arithmetically per <xref target="ISO8601-2"/> duration arithmetic, and (b) any longer Union or national law floor. The six-month period is read calendar-month-wise (the receipt expiry day is the same day-of-month six months later, with end-of-month rollover where the target month is shorter), not as a fixed day count.</t>
          <t>The 184-day figure (the maximum number of days in any rolling six-calendar-month window, worst case Aug-Jan, 31+30+31+30+31+31) is informative only; it expresses a safe day-count floor for hash-chain anchoring intervals and Audit Pack export windows where calendar-arithmetic is impractical at the producer layer. A Deployer that retains receipts strictly under the calendar-month rule above satisfies Article 26(6); a Deployer that uses 184 days as an internal day-count overestimate also satisfies it. A 183-day day-count floor is not endorsed by this profile: under a rolling six-calendar-month window 1 August to 31 January spans 184 days and 183 days is one day short. Where the Deployer is also a Financial Entity, the sectoral floor in <xref target="dora-retention"/> applies.</t>
        </section>
      </section>

      <section anchor="article-26"><name>EU AI Act Article 26 Binding</name>
        <section anchor="art26-1"><name>Article 26(1), in accordance with the instructions for use</name>
          <t><tt>policy_digest</tt> MUST resolve through <xref target="audit-pack"/> to a retained artefact (machine check). The Deployer SHOULD demonstrate consistency with the Provider's instructions for use (process check). Inability to perform the machine check is presumed non-compliance.</t>
        </section>
        <section anchor="art26-2"><name>Article 26(2), assign human oversight</name>
          <t>For any Action whose <tt>decision</tt> is <tt>allow</tt> and which the Deployer's risk management documentation marks as requiring human oversight, the Deployer MUST ensure that the receipt is either reviewed by a designated natural person within the period required by national law, or that a follow-on <tt>protectmcp:lifecycle</tt> Compliance Receipt records the absence of such review with a <tt>reason</tt> code. Both records MUST themselves be Compliance Receipts. This profile addresses the trigger and record of oversight; the competence, training, authority, and necessary support of the reviewer required by Article 26(2) remain the Deployer's separate responsibility.</t>
        </section>
        <section anchor="art26-5"><name>Article 26(5), monitor the operation</name>
          <t>A Deployer MUST be able to produce an Audit Pack covering any contiguous time window since the High-Risk AI System became operational.</t>
        </section>
        <section anchor="art26-6"><name>Article 26(6), keep the logs for at least six months</name>
          <t>Compliance Receipts under this binding MUST be retained for at least the period stated in <xref target="art12-retention"/>. Where the Deployer is also a Financial Entity, the longer sectoral floor in <xref target="dora-retention"/> applies.</t>
        </section>
      </section>

      <section anchor="dora-17"><name>DORA Article 17 Binding</name>
        <section anchor="dora-17-1"><name>Article 17(1), ICT-related incident management process</name>
          <t>A Compliance Receipt produced inside a Financial Entity's ICT environment may serve as the canonical record of an Action that triggered an ICT-related incident. <tt>action_ref</tt> MUST be carried into the Financial Entity's incident workflow as the primary correlation key.</t>
        </section>
        <section anchor="dora-17-2"><name>Article 17(2), record all ICT-related incidents and significant cyber threats</name>
          <t>The hash chain required by <xref target="hash-chain"/> supports the recording obligation of Article 17(2) by making after-the-fact alteration of recorded incidents detectable. The Financial Entity MUST be able to produce, on request, the chain segment covering the period of an incident, together with the anchor evidence that fixes the chain to wall-clock time.</t>
        </section>
        <section anchor="dora-17-3-b"><name>Article 17(3)(b), establish procedures to identify, track, log, categorise and classify ICT-related incidents</name>
          <t>For Actions identified as part of an ICT-related incident, the producing system MUST emit <tt>incident_class</tt>. The classification criteria are those set out in Article 18(1) of <xref target="DORA"/>, with further specification in <xref target="REG-2024-1772"/>. The canonical reporting enumeration to which <tt>incident_class</tt> flattens is bound by Annex II field 3.23 of <xref target="REG-2025-302"/> (see <xref target="extension-fields"/>). Implementations MUST publish a flattened mapping in the Audit Pack manifest as required by <xref target="extension-fields"/>.</t>
        </section>
        <section anchor="dora-retention"><name>Retention</name>
          <t>Article 17 of <xref target="DORA"/> does not itself set a uniform numeric retention floor. The five-year (1827-day) figure used by this profile derives from sectoral instruments that overlap DORA-scoped Financial Entities. Investment firms keep records of all services, activities and transactions under Article 16(6) of <xref target="MIFID2"/>, with Article 72 and Annex I of <xref target="REG-2017-565"/> fixing the form and content of those records. The explicit five-year retention period in <xref target="MIFID2"/> is set by Article 16(7) for records of telephone conversations and electronic communications, kept for a period of five years and, where requested by the competent authority, for a period of up to seven years.</t>
          <t>Records of customer due diligence and of transactions under Article 40 of <xref target="AMLD"/> are kept for five years after the end of the business relationship. The AMLD record-keeping regime is superseded, in respect of record retention, by Article 77 of <xref target="AMLR"/> from 10 July 2027, which preserves the five-year floor and adds a case-by-case extension up to a further five years where the competent authority so requires. Implementations operating across the AMLD-to-AMLR transition MUST satisfy whichever instrument is in force on the date of the Action.</t>
          <t>Compliance Receipts MUST be retained for the period required by applicable Union or national law; where a sectoral floor applies, retention MUST equal or exceed the longest applicable floor. Absent a more specific rule, this profile RECOMMENDS 1827 days from the date of the Action (the worst-case rolling five-calendar-year window contains two leap days, so 1827 days satisfies "five years" regardless of the calendar years over which the window falls). Anchor evidence MUST be retained for the same period. Verification keys whose lifetime expires within the retention window MUST have their public components retained so that historical signatures remain verifiable.</t>
        </section>
      </section>
    </section>

    <section anchor="us-bindings"><name>United States Bindings</name>
      <section anchor="nist-ai-rmf"><name>NIST AI RMF Binding</name>
        <t><xref target="NIST-AI-RMF"/> is a voluntary framework. Adoption of this profile, on its own, does not establish conformity with the AI RMF; it provides a tamper-evident receipt substrate that an AI RMF program can use as evidence under the MEASURE function and as a structured input to the GOVERN, MAP, and MANAGE functions. <xref target="NIST-GENAI-PROFILE"/> applies the AI RMF functions to generative AI; the profile bindings below apply to generative and non-generative AI agent deployments alike unless explicitly noted.</t>
        <section anchor="rmf-govern"><name>GOVERN function</name>
          <t>The GOVERN function requires that organizations document AI policies and procedures. The combination of <tt>policy_digest</tt> and the Audit Pack manifest provides a machine-readable binding between every Action and the policy artefact in force at the time of the Action. A change to the policy artefact MUST produce a new <tt>policy_digest</tt> value (per <xref target="policy-digest"/>); the Audit Pack therefore records every policy change in a tamper-evident manner.</t>
        </section>
        <section anchor="rmf-map"><name>MAP function</name>
          <t>The MAP function requires that the context, capabilities, and risks of an AI system be characterised. The combination of <tt>type</tt>, <tt>tool_name</tt>, <tt>action_ref</tt>, and <tt>iteration_id</tt> SHOULD be sufficient for an auditor to reconstruct the operational context of any Action without dereferencing the underlying payload.</t>
        </section>
        <section anchor="rmf-measure"><name>MEASURE function</name>
          <t>The MEASURE function requires that AI risks and impacts be analysed and tracked over time. The hash-chain linkage required by <xref target="hash-chain"/> provides tamper-evident continuity of the receipt stream over the AI system's operational lifetime, satisfying the traceability prerequisite of MEASURE.</t>
        </section>
        <section anchor="rmf-manage"><name>MANAGE function</name>
          <t>The MANAGE function requires that AI risks be prioritised and acted upon based on projected impact. The <tt>risk_class</tt> extension field carries the Deployer's risk classification of the Action; together with <tt>decision</tt>, <tt>reason</tt>, and <tt>policy_digest</tt>, it supports prioritisation and incident response without requiring the verifier to re-derive risk from the underlying payload.</t>
        </section>
      </section>

      <section anchor="colorado-ai-act"><name>Colorado AI Act (SB 24-205) Binding</name>
        <t><xref target="COLORADO-AI-ACT"/> imposes deployer obligations effective June 30, 2026 (per Senate Bill 25B-004, which postponed the original February 1, 2026 effective date). The Act regulates the deployment of High-Risk AI Systems and the prevention of algorithmic discrimination.</t>
        <section anchor="co-1703-2"><name>Section 6-1-1703(2), risk management policy and program</name>
          <t>Section 6-1-1703(2) requires deployers to implement a risk management policy and program for the High-Risk AI System. <tt>policy_digest</tt> MUST resolve through <xref target="audit-pack"/> to the deployer's risk management policy artefact in force at the time of the Action. Where the Deployer classifies an Action as risk-bearing under that policy, the receipt MUST carry a <tt>risk_class</tt> extension field.</t>
        </section>
        <section anchor="co-1703-3"><name>Section 6-1-1703(3), impact assessment</name>
          <t>Section 6-1-1703(3) requires deployers to complete an impact assessment annually and within 90 days after any intentional and substantial modification of the High-Risk AI System. The combination of <tt>type</tt>, <tt>policy_digest</tt>, and <tt>previousReceiptHash</tt> MUST be sufficient for an auditor to identify, by query alone, the receipts that span the period covered by an impact assessment, including any policy changes within that period.</t>
        </section>
        <section anchor="co-1703-7"><name>Section 6-1-1703(7), notice of algorithmic discrimination</name>
          <t>Where a Deployer determines that a High-Risk AI System has caused or is reasonably likely to have caused algorithmic discrimination, the producing system SHOULD record that determination as a <tt>protectmcp:lifecycle</tt> Compliance Receipt naming the determination, the affected receipts by <tt>action_ref</tt>, and the policy or risk-management response with a <tt>reason</tt> code.</t>
        </section>
      </section>

      <section anchor="texas-traiga"><name>Texas Responsible AI Governance Act (HB 149) Binding</name>
        <t><xref target="TEXAS-TRAIGA"/> takes effect January 1, 2026. The Act adopts an intent-based liability framework for the development and deployment of AI systems and provides a safe harbor at Section 552.105(e)(2)(D) of the Texas Business and Commerce Code for organisations that substantially comply with the most recent version of <xref target="NIST-GENAI-PROFILE"/>, or another nationally or internationally recognized risk management framework for AI systems, and operate an internal review process.</t>
        <section anchor="tx-safe-harbor"><name>Safe-harbor evidentiary support</name>
          <t>Where a Deployer relies on the safe-harbor provision of HB 149 by substantially complying with <xref target="NIST-GENAI-PROFILE"/>, the Audit Pack MAY be presented as evidence of that compliance. The bindings of <xref target="nist-ai-rmf"/> apply, with the additional Generative AI Profile bindings of <xref target="NIST-GENAI-PROFILE"/>.</t>
        </section>
        <section anchor="tx-prohibited-use"><name>Prohibited-use detection</name>
          <t>Receipts whose <tt>decision</tt> is <tt>deny</tt> with a <tt>reason</tt> code drawn from a vocabulary documenting the Act's prohibited-use categories under Section 552.052 of the Texas Business and Commerce Code added by HB 149 (incitement or encouragement of physical self-harm including suicide, harm to another person, or engagement in criminal activity) MUST be retained for the period stated in <xref target="hipaa-retention"/> or the longer period required by Texas law, whichever is greater.</t>
        </section>
      </section>

      <section anchor="hipaa"><name>HIPAA Security Rule Binding (45 CFR Part 164, Subpart C)</name>
        <t><xref target="HIPAA-SECURITY"/> applies to Covered Entities (HIPAA) that handle electronic protected health information. The bindings below apply only to receipts whose underlying Actions reference electronic protected health information.</t>
        <section anchor="hipaa-164-312-b"><name>45 CFR 164.312(b), audit controls</name>
          <t>45 CFR 164.312(b) requires implementation of "hardware, software, and/or procedural mechanisms that record and examine activity in information systems that contain or use electronic protected health information". The combination of <tt>type</tt>, <tt>action_ref</tt>, <tt>tool_name</tt>, and the hash-chain linkage required by <xref target="hash-chain"/> satisfies the recording requirement; the verification rules of <xref target="mandatory-checks"/> satisfy the examination requirement.</t>
        </section>
        <section anchor="hipaa-retention"><name>45 CFR 164.316(b)(2), six-year retention</name>
          <t>45 CFR 164.316(b)(2) (and in particular the subparagraph 164.316(b)(2)(i)) requires that the documentation required by 45 CFR 164.316(b)(1) be retained "for 6 years from the date of its creation or the date when it last was in effect, whichever is later". The audit-log content produced under 45 CFR 164.312(b) is not itself documentation required by 164.316(b)(1); the Security Rule does not set an explicit retention floor for individual audit-log records. By analogy with the six-year floor that 164.316(b)(2) places on the policies and procedures that govern audit-log generation, this profile applies the same six-year floor to Compliance Receipts whose underlying Actions reference electronic protected health information.</t>
          <t>Records covered by the HIPAA Security Rule audit-trail retention MUST be retained for six years from the date of creation or the date when last in effect, whichever is later, per 45 CFR 164.316(b)(2). This profile expresses that floor as 2192 days from the later of (a) the date of the Action and (b) the date the policy artefact referenced by <tt>policy_digest</tt> ceased to be in effect: 2192 is the maximum number of days in any rolling six-calendar-year window (worst case spans two leap days, e.g. 2024-2030 contains February 29 of 2024 and 2028, yielding 6*365+2 = 2192 days). The six-year analogy floor is grounded in 164.316(b)(2); a Covered Entity that retains receipts strictly under 164.316(b)(2)(i) bound only to the policy artefact's creation-or-cessation date MAY do so when no longer audit-log floor is established by separate Union, state, or sectoral law. Verification keys whose lifetime expires within the retention window MUST have their public components retained so that historical signatures remain verifiable.</t>
        </section>
      </section>

      <section anchor="nydfs"><name>NYDFS Cybersecurity Regulation Binding (23 NYCRR Part 500)</name>
        <t><xref target="NYDFS-500"/> applies to Covered Entities (NYDFS) operating under New York Banking, Insurance, or Financial Services Law. The bindings below apply only to receipts produced by such Covered Entities.</t>
        <section anchor="nydfs-500-06"><name>23 NYCRR 500.6, audit trail</name>
          <t>23 NYCRR 500.6(a) requires Covered Entities to securely maintain systems that, to the extent applicable and based on its risk assessment, (1) are designed to reconstruct material financial transactions, and (2) include audit trails designed to detect and respond to cybersecurity events that have a reasonable likelihood of materially harming any material part of the normal operations of the Covered Entity. The hash chain required by <xref target="hash-chain"/> together with the anchor evidence required by <xref target="anchoring"/> satisfies the tamper-evidence prerequisite of the audit-trail obligation.</t>
        </section>
        <section anchor="nydfs-500-17"><name>23 NYCRR 500.17, notices to superintendent</name>
          <t>23 NYCRR 500.17(a)(1) requires that "Each covered entity shall notify the superintendent electronically in the form set forth on the department's website as promptly as possible but in no event later than 72 hours after determining that a cybersecurity incident has occurred at the covered entity, its affiliates, or a third-party service provider." The reporting trigger is a Cybersecurity Incident under 23 NYCRR 500.1(g), not any Cybersecurity Event under 500.1(f). For Actions identified as part of such an Incident, the producing system MUST emit <tt>incident_class</tt> with a value indicating Cybersecurity Incident under 23 NYCRR 500.1(g), and the Covered Entity MUST be able to produce, on request, the chain segment covering the period of the Incident together with the anchor evidence that fixes the chain to wall-clock time.</t>
        </section>
        <section anchor="nydfs-retention"><name>23 NYCRR 500.6 retention</name>
          <t>23 NYCRR 500.6(b) requires that "Each Covered Entity shall maintain records required by this section for not fewer than five years." The five-year floor applies uniformly to records required by paragraph (a)(1) (designed to reconstruct material financial transactions) and to records required by paragraph (a)(2) (audit trails designed to detect and respond to cybersecurity events that have a reasonable likelihood of materially harming any material part of the normal operations of the Covered Entity). Compliance Receipts produced under this binding MUST be retained for at least 1827 days from the date of the Action (the worst-case rolling five-calendar-year window contains two leap days).</t>
        </section>
      </section>

      <section anchor="sec"><name>SEC Broker-Dealer Recordkeeping Binding (17 CFR 240.17a-4)</name>
        <t><xref target="SEC-17A-4"/> applies to Broker-Dealers, Security-Based Swap Dealers, and Major Security-Based Swap Participants. The bindings below apply only to receipts produced inside such entities.</t>
        <section anchor="sec-17a-4-f"><name>17 CFR 240.17a-4(f), electronic recordkeeping system</name>
          <t>The November 3, 2022 amendments to 17 CFR 240.17a-4 (compliance date May 3, 2023) added an audit-trail alternative to the prior write-once-read-many (WORM) electronic recordkeeping requirement. The audit-trail alternative requires that the electronic recordkeeping system permit the recreation of an original record if it is modified or deleted. The hash-chain linkage required by <xref target="hash-chain"/> together with the retention rule in <xref target="sec-retention"/> and the anchor evidence required by <xref target="anchoring"/> satisfies the audit-trail alternative when the Compliance Receipt is the system-of-record for a regulated record.</t>
        </section>
        <section anchor="sec-retention"><name>17 CFR 240.17a-4(a) and (b) retention</name>
          <t>17 CFR 240.17a-4(a) requires preservation of certain records for not less than 6 years, the first two years in an easily accessible place. 17 CFR 240.17a-4(b) requires preservation of a different list of records for not less than three years, the first two years in an easily accessible place. Compliance Receipts that constitute or support a record listed in 17 CFR 240.17a-4(a) MUST be retained for at least 2192 days from the date of the Action, applying the same six-year worst-case methodology as <xref target="hipaa-retention"/>; receipts that constitute or support a record listed only in 17 CFR 240.17a-4(b) MUST be retained for at least 1096 days from the date of the Action (the worst-case rolling three-calendar-year window contains one leap day). Where both apply, the longer period applies.</t>
        </section>
      </section>

      <section anchor="circia"><name>CIRCIA Binding (Cyber Incident Reporting for Critical Infrastructure Act of 2022)</name>
        <t><xref target="CIRCIA"/> requires Covered Entities (CIRCIA) to report Covered Cyber Incidents to the Cybersecurity and Infrastructure Security Agency within 72 hours of reasonable belief that the incident has occurred, and to report ransom payments within 24 hours. The reporting obligations take effect upon publication of the final rule. Pending publication, the bindings below apply on a voluntary basis.</t>
        <section anchor="circia-incident"><name>Covered Cyber Incident reporting support</name>
          <t>For Actions identified as part of a Covered Cyber Incident, the producing system MUST emit <tt>incident_class</tt> with a value indicating Covered Cyber Incident under <xref target="CIRCIA"/>. The Covered Entity MUST be able to produce, on request, the chain segment covering the period of the incident together with the anchor evidence that fixes the chain to wall-clock time.</t>
        </section>
        <section anchor="circia-retention"><name>Records related to a Covered Cyber Incident report</name>
          <t>Section 2242(a)(4) of the Homeland Security Act of 2002, as enacted by <xref target="CIRCIA"/> and codified at 6 U.S.C. 681b(a)(4), requires Covered Entities to preserve data relevant to a Covered Cyber Incident or ransom payment in accordance with procedures established in the final rule. CISA's notice of proposed rulemaking at 89 FR 23644 (April 4, 2024), proposed Section 226.13(c), proposes a preservation period of not less than two years measured from the submission of the most recently required CIRCIA report (or the date that submission would have been required absent a preservation exception under proposed Section 226.4(a)); this profile uses that proposed floor pending publication of the final rule.</t>
          <t>Records covered by CIRCIA preservation MUST be retained for two years from the submission of the most recently required CIRCIA report under 6 U.S.C. 681b(c)(2). Compliance Receipts that are referenced in a CIRCIA report or that the Covered Entity reasonably anticipates will be so referenced MUST be retained for the longer of (a) the period established by the final rule and (b) two years from the submission of the most recently required CIRCIA report (or the date that submission would have been required absent a preservation exception), per proposed Section 226.13(c) of the CIRCIA NPRM at 89 FR 23644 (April 4, 2024). Covered Entities MUST NOT measure the retention floor from the date of the underlying Action; an Action detected and reported months later carries a preservation window that runs forward from the report submission date.</t>
        </section>
      </section>
    </section>

    <section anchor="audit-pack"><name>Audit Pack Composition</name>
      <t>This section is informative. It describes the contents of an Audit Pack as introduced in <xref target="conventions"/>.</t>
      <t>An Audit Pack contains the following items.</t>
      <ul>
        <li>The set of Compliance Receipts covered by the requested time window, in the canonical envelope form defined by <xref target="ACTA-RECEIPTS"/>.</li>
        <li>The chain commitments that link the receipts: for each receipt, the value of <tt>previousReceiptHash</tt> and the recomputed digest of the predecessor envelope.</li>
        <li>The anchor evidence: <xref target="RFC3161"/> tokens, OpenTimestamps proofs, or both. Each anchor item MUST be associated, by hash, with the receipt or aggregate it covers.</li>
        <li>The trust anchor metadata that identifies the Deployer or other regulated entity associated with each <tt>issuer_id</tt> value.</li>
        <li>The verification key material for every <tt>kid</tt> value present, in a form that does not require online retrieval.</li>
        <li>Vocabularies referenced by <tt>reason</tt>, <tt>risk_class</tt>, <tt>incident_class</tt>, and extension fields, embedded as JSON arrays with a stable identifier. The Audit Pack MUST expose a digest-resolution facility that, given a <tt>policy_digest</tt>, returns the retained artefact.</li>
        <li>A regime mapping document that names which receipts the producer asserts as evidence under any of the regimes addressed by Sections 5 and 6 of this document (EU AI Act Article 12, EU AI Act Article 26, DORA Article 17, NIST AI RMF, Colorado AI Act, Texas Responsible AI Governance Act, NYDFS Part 500, HIPAA Security Rule, SEC Rule 17a-4, CIRCIA).</li>
        <li>The chain heads valid at the start and end of the time window, signed by the Deployer or other regulated entity.</li>
      </ul>
      <t>An Audit Pack MUST itself be signed per the <xref target="ACTA-RECEIPTS"/> algorithm registry. The manifest MUST include <tt>bundle_digest</tt>, <tt>bundle_signature</tt>, <tt>bundle_public_key</tt>, and <tt>algorithm_registry_version</tt>.</t>
      <t>The following manifest-level fields SHOULD appear on an Audit Pack bundle when the underlying receipt stream exposes the corresponding semantics. Each is informative and does not alter the wire shape of individual receipts.</t>
      <dl>
        <dt><tt>regime_mapping_disclaimer</tt>:</dt>
        <dd>String emitted on bundles whose per-receipt regime predicates derive from mapping logic the original producing system did not sign. The value identifies the producer of the mapping, the document version under which it was computed, and a disclaimer that the regime-satisfaction flags are advisory and remain subject to the verifier's own check against Sections 5 and 6.</dd>
        <dt><tt>stale_pending</tt>:</dt>
        <dd>Boolean flag set per bundle entry whose anchor evidence is still <tt>pending</tt> after the bound of <xref target="anchoring"/> (7 days for OpenTimestamps; synchronous for RFC 3161). When <tt>true</tt>, the bundled receipt is non-conformant per <xref target="anchoring"/>, and a Compliance Verifier consumes the flag to drive <tt>anchor_valid_*</tt> false in its per-axis report (see <xref target="reporting"/>). A verify endpoint over the same bundle SHOULD surface <tt>stale_pending</tt> in its response.</dd>
      </dl>
    </section>

    <section anchor="verifier"><name>Verifier Behaviour</name>
      <t>A verifier conformant to this profile is referred to as a Compliance Verifier.</t>
      <section anchor="mandatory-checks"><name>Mandatory Checks</name>
        <t>A Compliance Verifier MUST perform all of the following checks before treating a receipt as a Compliance Receipt.</t>
        <ul>
          <li>Verify the signature using the algorithm declared in <tt>signature.alg</tt>, in accordance with <xref target="ACTA-RECEIPTS"/>.</li>
          <li>Resolve the verification key through one of the key-distribution mechanisms described in Section 4.3 of <xref target="ACTA-RECEIPTS"/> (well-known JWK Set or out-of-band distribution), or through Audit Pack trust-anchor metadata. The verifier MUST NOT trust a verification key embedded in the receipt envelope.</li>
          <li>Verify that all fields marked REQUIRED by <xref target="field-profile"/> are present and well-formed.</li>
          <li>Verify the hash-chain linkage by recomputing SHA-256 over the canonical signing-input bytes of the immediately preceding receipt (the JCS-canonical serialization of the predecessor's signed payload object, per <xref target="hash-chain"/>) and comparing the lowercase hex encoding to <tt>previousReceiptHash</tt>.</li>
          <li>Verify at least one anchor: an <xref target="RFC3161"/> token, an <xref target="OPENTIMESTAMPS"/> commitment, or both. The anchor MUST cover the signed envelope as it appears in the receipt. The verifier MUST cryptographically re-verify the anchor against the signed envelope; presence of anchor metadata without a successful cryptographic check MUST NOT yield "valid".</li>
          <li>Verify the future-skew bound on <tt>issued_at</tt> per <xref target="issued-at"/>. Past skew MUST NOT cause non-conformance when the receipt is within retention.</li>
          <li>Verify that <tt>policy_digest</tt> resolves through <xref target="audit-pack"/>. A digest computed over a nonced or otherwise mixed-input form (for example, SHA-256(nonce || JCS(artefact))) MUST NOT be treated as <tt>policy_digest</tt>; the digest scope is the canonical form of the artefact alone. The verifier MUST recompute SHA-256 over the canonical form of the resolved artefact as documented in the Audit Pack manifest, and compare; for JSON artefacts the canonical form is JCS per <xref target="RFC8785"/>.</li>
        </ul>
        <t>A receipt that fails any of these checks MUST be reported as non-conformant.</t>
      </section>
      <section anchor="optional-checks"><name>Optional Checks</name>
        <t>A Compliance Verifier MAY additionally perform any of the following.</t>
        <ul>
          <li>Cross-check the <tt>issuer_id</tt> against an external registry (LEI, EIN, CIK, NPI, GLEIF, or a Deployer-published list).</li>
          <li>Resolve the policy artefact referenced by <tt>policy_digest</tt> and compare it to a Provider-supplied or Deployer-supplied reference policy.</li>
          <li>Recompute the chain head and compare it to a Deployer-published value.</li>
          <li>Validate <tt>incident_class</tt> (each element if encoded as an array) and <tt>risk_class</tt> extension values against the vocabularies referenced in the Audit Pack.</li>
        </ul>
      </section>
      <section anchor="reporting"><name>Reporting</name>
        <t>A Compliance Verifier SHOULD produce a structured per-receipt report that names the regime bindings the receipt satisfies and the outcome of the per-axis checks the verifier performed. The following fields SHOULD be emitted; the axes are independent and consumers MUST NOT collapse them into a single boolean before display.</t>
        <dl>
          <dt><tt>regimes_satisfied</tt>:</dt>
          <dd>Array of short stable regime identifiers drawn from the regimes listed in <xref target="audit-pack"/> (for example <tt>eu_ai_act</tt>, <tt>dora</tt>, <tt>nist_ai_rmf</tt>, <tt>colorado_ai</tt>, <tt>texas_traiga</tt>, <tt>hipaa_security</tt>, <tt>nydfs_500</tt>, <tt>sec_17a4a</tt>, <tt>sec_17a4b</tt>, <tt>circia</tt>). The set is open-ended; consumers MUST treat unknown identifiers as informational. Where this field is inherited from a producer-side mapping in the bundle, the bundle-level <tt>regime_mapping_disclaimer</tt> of <xref target="audit-pack"/> applies.</dd>
          <dt><tt>anchor_valid_ots</tt>:</dt>
          <dd>Boolean. <tt>true</tt> when an <xref target="OPENTIMESTAMPS"/> anchor is present, has upgraded to the Bitcoin block attestation within the 7-day bound of <xref target="anchoring"/>, and re-verifies cryptographically against the signed envelope; otherwise <tt>false</tt> (including the case where the only present anchor is RFC 3161).</dd>
          <dt><tt>anchor_valid_rfc3161</tt>:</dt>
          <dd>Boolean. <tt>true</tt> when an <xref target="RFC3161"/> token is present, carries an ESSCertIDv2 per <xref target="RFC5816"/> where required, and re-verifies cryptographically against the signed envelope; otherwise <tt>false</tt>.</dd>
          <dt><tt>policy_digest_resolved</tt>:</dt>
          <dd>Boolean. <tt>true</tt> when <tt>policy_digest</tt> resolved to a retained artefact whose JCS-canonical SHA-256 matches the receipt value, per <xref target="mandatory-checks"/>; <tt>false</tt> on absence, resolution failure, or digest mismatch.</dd>
          <dt><tt>duplicate_emission_candidate</tt>:</dt>
          <dd>Boolean. <tt>true</tt> when at least one other receipt sharing <tt>action_ref</tt> and <tt>issuer_id</tt> has been observed in the same Audit Pack or in a verifier-maintained index; otherwise <tt>false</tt>. The axis is informational; this profile does not require verifiers to maintain a cross-receipt index. An absent index MUST report <tt>false</tt> rather than omit the axis, so consumers learn "no duplicate" from the value and learn "axis unknown" only from the verifier's documented capability set.</dd>
        </dl>
        <t>A receipt may carry <tt>anchor_valid_ots</tt>=true and <tt>anchor_valid_rfc3161</tt>=false (or vice versa) and still satisfy the mandatory anchor check of <xref target="anchoring"/>, which requires only one valid anchor. Where a receipt carries <tt>counterparty_binding</tt> per <xref target="counterparty-binding"/>, the verifier SHOULD additionally emit the outcome of the check of <xref target="counterparty-binding-verifier"/>; this profile reserves a stable field identifier for that axis pending implementation experience.</t>
      </section>
    </section>

    <section anchor="security"><name>Security Considerations</name>
      <t>This profile inherits all of the security considerations of <xref target="ACTA-RECEIPTS"/>. The following considerations are specific to the compliance binding.</t>
      <section anchor="tamper"><name>Tamper Resistance</name>
        <t>The hash-chain linkage required by <xref target="hash-chain"/> provides tamper-evidence at the chain level. An adversary who removes a receipt from the middle of the chain MUST recompute and re-sign every subsequent envelope. The anchor evidence required by <xref target="anchoring"/> binds segments of the chain to wall-clock time, raising the cost of a re-signing attack.</t>
        <t>Implementations SHOULD anchor at intervals no longer than 24 hours. Implementations operating under DORA Article 17, 23 NYCRR 500.17, or <xref target="CIRCIA"/> SHOULD anchor at intervals no longer than one hour, given the four-hour initial-notice deadline (with 72-hour intermediate-report and one-month final-report bounds) per DORA Article 17 and the RTS in <xref target="REG-2025-301"/>, the 72-hour notification clock under 23 NYCRR 500.17, and the 72-hour CIRCIA covered-cyber-incident reporting deadline that will apply once the CIRCIA final rule takes effect.</t>
        <t>A deployment that uses only the signature, without chain linkage and anchoring, can be rolled back by an insider with control of the signing key for the period between the deletion and the next anchor. The MUST clauses of <xref target="hash-chain"/> and <xref target="anchoring"/> close that window.</t>
      </section>
      <section anchor="chain-availability"><name>Chain Availability Under Single-Linear Per-Agent Serialization</name>
        <t>This section is informative. The single-linear per-agent chain requirement of <xref target="hash-chain"/> serializes receipt emission for a given <tt>issuer_id</tt> through a single predecessor pointer. A denial-of-service against the predecessor pointer (database row lock contention, network partition between the emitter and the predecessor store, slow IO, or an adversary deliberately holding the chain-tail lock) therefore bounds the per-agent emission throughput, because every new receipt MUST resolve the digest of the immediately prior receipt before it can be linked. A partial-write failure between predecessor-pointer commit and signature commit can additionally produce chain-head ambiguity if not handled defensively.</t>
        <t>Issuers SHOULD use a bounded predecessor-lookup timeout (operator-tuned, typically on the order of seconds rather than tens of seconds) and SHOULD emit a structured audit event with type <tt>protectmcp:lifecycle</tt> and a stable <tt>reason</tt> code (RECOMMENDED: <tt>chain_emission_blocked</tt>) when the timeout fires, rather than silently dropping the receipt or stalling caller threads. Issuers SHOULD additionally document a chain-head recovery procedure for crashed emitters: on restart, the issuer re-reads the predecessor row, verifies that no orphan signature exists for the next sequence position, and resumes emission. Operators that require parallel per-issuer throughput beyond what a single linear chain sustains MUST use distinct <tt>issuer_id</tt> values per parallel path, with separate signing keys and chains rooted at the all-zero genesis value, per the rule in <xref target="hash-chain"/>.</t>
        <t>The threat profile here is availability, not confidentiality or integrity: a successful chain-availability attack delays or drops emission, but it cannot tamper with already-emitted receipts (those are protected by <xref target="tamper"/>) and it cannot forge receipts (those are protected by <xref target="key-compromise"/>). The <tt>chain_emission_blocked</tt> lifecycle receipt is itself a Compliance Receipt and therefore links into the chain once emission resumes, so the gap is detectable rather than silent.</t>
      </section>
      <section anchor="key-compromise"><name>Key Compromise</name>
        <t>A Compliance Receipt is only as trustworthy as the key that signed it. On suspected compromise of an issuer key, the Deployer MUST publish a revocation notice that names the key, the time of suspected compromise, and the chain head at that time. Receipts signed by the compromised key after the named time MUST NOT be treated as Compliance Receipts.</t>
        <t>Verifiers MUST consult revocation metadata supplied with the Audit Pack and MUST reject Compliance Receipts whose signing key was revoked at or before <tt>issued_at</tt>.</t>
      </section>
      <section anchor="long-term"><name>Retention and Long-Term Verifiability</name>
        <t>The longest retention floor in this profile is 2192 days (six calendar years), set by <xref target="hipaa"/> and <xref target="sec"/>; the EU side has a parallel five-year (1827-day) floor under <xref target="dora-17"/>. Both exceed the typical operational crypto-period of a signing key under recommended key-management practice. Implementations SHOULD use ML-DSA-65 from the <xref target="ACTA-RECEIPTS"/> algorithm registry (<xref target="FIPS204"/>) for receipts expected to be verified after the cryptographic lifetime of classical signature schemes ends. Implementations MUST retain public key material for the entire retention window.</t>
      </section>
      <section anchor="privacy"><name>Privacy</name>
        <t><xref target="ACTA-RECEIPTS"/> prohibits the inclusion of raw prompts, tool arguments, and credentials in the signed payload. This profile extends that prohibition to the extension fields defined in this document. The <tt>risk_class</tt> and <tt>incident_class</tt> values MUST be drawn from controlled vocabularies and MUST NOT carry free-text personal data.</t>
        <t>Where the underlying Action references a data subject, the <tt>payload_digest</tt> field MUST cover the data; the data itself MUST be held in a separate store that respects the data subject's rights under applicable law (including but not limited to the General Data Protection Regulation for EU data subjects, the California Consumer Privacy Act and Virginia Consumer Data Protection Act for the corresponding US states, and the HIPAA Privacy Rule where electronic protected health information is involved). A request for erasure that is granted under applicable data protection law MUST be reflected by deletion of the referenced payload, not by deletion of the receipt; the receipt remains as evidence that an Action occurred and was governed by a named policy at a named time.</t>
      </section>
      <section anchor="anchor-trust"><name>Anchor Trust</name>
        <t>The trust assumptions of an anchor depend on the anchor <tt>type</tt>. <xref target="RFC3161"/> timestamp tokens depend on the trust placed in the named Time Stamping Authority. OpenTimestamps commitments depend on the inclusion of the commitment in a public Bitcoin block. A Compliance Verifier SHOULD treat the simultaneous presence of both anchor types as stronger evidence than the presence of only one.</t>
      </section>
      <section anchor="replay"><name>Replay</name>
        <t>A Compliance Receipt is bound to a single Action via <tt>action_ref</tt>. Replay of a Compliance Receipt against a different Action is detectable by <tt>action_ref</tt> mismatch. The 300-second <tt>issued_at</tt> skew bound stated in <xref target="issued-at"/> limits the window in which a freshly-replayed receipt can be presented as recent.</t>
        <t>Where the verifier supports it, two receipts sharing <tt>action_ref</tt> and <tt>issuer_id</tt> SHOULD be flagged as a candidate duplicate-emission event for human review. This profile does not require verifiers to maintain a cross-receipt index; deployers needing duplicate-emission detection should arrange it at the Audit Pack production layer.</t>
      </section>
      <section anchor="cross-regime"><name>Cross-Regime Conflict</name>
        <t>Where the same Action is in scope of more than one regime addressed by this document, the producing system MUST satisfy the union of the applicable requirements. Where a SHOULD clause in one regime conflicts with a MUST clause in another, the MUST clause prevails. Where two MUST clauses conflict, the producing system MUST refuse to issue the receipt and MUST log the refusal as a protectmcp:lifecycle Compliance Receipt.</t>
      </section>
      <section anchor="algorithm-agility"><name>Algorithm Agility</name>
        <t>This profile inherits its algorithm registry from <xref target="ACTA-RECEIPTS"/>. Implementations MUST treat the verification of a historical receipt according to the algorithm registry that was in force at <tt>issued_at</tt>, not the registry in force at the time of verification, provided that the signing key was not revoked.</t>
      </section>
      <section anchor="issuer-misrep"><name>Issuer-Misrepresentation Residual</name>
        <t>Per-agent hash chains under <xref target="hash-chain"/> detect tampering inside a single issuer's stream but not the cross-agent attack in which a compromised intermediary silently swaps payload bytes between two honest agents. Both per-agent chains validate; <tt>action_ref</tt> is a correlation anchor, not a cryptographic binding (<xref target="ACTA-RECEIPTS"/> Section 2.2). Without a cross-agent binding primitive, a regulator obtains no cryptographic answer to "did the acknowledging agent acknowledge the bytes the originating agent actually sent". This profile defines <tt>counterparty_binding</tt> (<xref target="counterparty-binding"/>) as the partial mitigation; the following residuals remain.</t>
        <ul>
          <li>Endpoint collusion. If both signing keys are compromised by the same attacker, the attacker produces a coordinated forgery; no signature scheme defends against this case.</li>
          <li>Intermediary holds the originating agent's key. In hosted-agent deployments where the intermediary possesses the originating agent's private key, it can sign anything as either party. Remote attestation of key origin is the appropriate countermeasure and is out of scope here.</li>
          <li>Originator offline at verification time. <xref target="counterparty-binding-verifier"/> requires the originating envelope to be retrievable; if unpublished, offline, or rate-limited, the binding becomes unverifiable (liveness loss, observable as failure).</li>
          <li>Fan-out witness gap. When an originator broadcasts to N acknowledgers, each emits an independent pairwise binding; none witnesses any other. Append-only log profiles (future SCITT-style transparency) are deferred to a later revision.</li>
          <li>Key rotation orphan. If the originating agent rotates keys after emission but before an acknowledger binds it, the storage obligation of <xref target="counterparty-binding-verifier"/> still requires the old envelope to remain retrievable; if retention discipline fails, the binding orphans.</li>
          <li>Privacy of envelope hashes. <tt>envelope_hash</tt> is computed over the full signed bytes including A's signature; an observer of B's receipt learns a stable identifier for A's exact action and therefore can correlate B's behaviour across receipts even when A's payload is otherwise confidential. Where this correlation is unacceptable, a commitment scheme (for example, HMAC over the envelope with a per-counterparty key disclosed only to the verifier) is appropriate; this profile does not specify one.</li>
          <li>Real-time prevention. <tt>counterparty_binding</tt> is detective, not preventive: B has already accepted the bytes by the time the binding is signed. Verifiers detect tampering only at audit time; the in-flight bytes were not blocked. Where prevention is required, transport-level integrity per <xref target="trust-boundary"/> is the appropriate primitive in addition to (not instead of) this profile.</li>
          <li>Payload-content semantics. The binding proves byte equality, not semantic equality. An intermediary that re-encodes A's bytes into a different but JCS-equivalent canonical form is detected (the SHA-256 differs); an intermediary that swaps A's bytes for entirely different bytes that B's policy happens to interpret as semantically equivalent is detected too. But an intermediary that swaps A's bytes for an A-signed REPLAY of a prior valid envelope from A is not detected by this binding alone; replay protection requires that the verifier also check <tt>action_ref</tt> and <tt>previousReceiptHash</tt> uniqueness within the chain segment.</li>
        </ul>
      </section>
      <section anchor="trust-boundary"><name>Cross-Agent Integrity Trust Boundary</name>
        <t>This section is informative. It records operator guidance for cases where channel-level protection is the only available defence and <tt>counterparty_binding</tt> per <xref target="counterparty-binding"/> has not yet been adopted by both endpoints. For channels between named principals, implementers SHOULD secure the channel using mutually authenticated TLS 1.3 per <xref target="RFC8446"/>; MAY use the tls-exporter channel binding per <xref target="RFC9266"/> derived via <xref target="RFC5705"/> where higher channel uniqueness is required; and MAY layer HTTP Message Signatures per <xref target="RFC9421"/> where intermediaries perform legitimate transformations.</t>
        <t>Operators MUST NOT interpret transport-layer security alone as evidence of cross-agent byte equality. Only <tt>counterparty_binding</tt> produces application-layer, signed, replay-after-the-fact evidence answering that question. Topologies where the intermediary terminates TLS (CDN edges, MCP servers, message buses, orchestrators) defeat transport-layer integrity against the threat case of <xref target="issuer-misrep"/>; in those topologies <tt>counterparty_binding</tt> is the only defence this profile offers, and the absence of channel-binding evidence in the Audit Pack SHOULD be documented as a known residual.</t>
      </section>
      <section anchor="compromised-intermediary"><name>Compromised Intermediary Between Two Honest Endpoints</name>
        <t>This section is informative. Where an Action travels from a sending agent A to a receiving agent B through one or more intermediary processes M, and where M is compromised in such a way that M presents byte sequence X to A and a different byte sequence X' to B, neither A's nor B's cryptographic signature detects the divergence in isolation: each endpoint signs the bytes it observed, and each endpoint's per-agent hash chain per <xref target="hash-chain"/> remains internally valid. Absent the <tt>counterparty_binding</tt> primitive this profile introduces, the only available cross-agent primitive is <tt>action_ref</tt> as a SHA-256 join key per <xref target="action-ref"/>; both A's chain and B's chain remain valid in isolation, and divergence is only recoverable through a regulator-driven post-hoc comparison of the two chains.</t>
        <t><tt>counterparty_binding</tt> introduced in <xref target="counterparty-binding"/> closes the case where M silently swaps bytes between two honest endpoints A and B. An acknowledging receipt under this binding is REQUIRED to carry an <tt>envelope_hash</tt> computed over the exact byte stream B received (SHA-256(A's envelope) under the digest-scope rule of <xref target="counterparty-binding-wire"/>). A verifier resolves <tt>receipt_ref</tt> to A's stored envelope, recomputes the digest, and compares; a mismatch indicates that the bytes B signed are not the bytes A signed, and the acknowledging receipt MUST be reported non-conformant per <xref target="counterparty-binding-verifier"/>. The binding is detective rather than preventive: it does not stop M from performing the swap in flight, but it produces signed, replay-after-the-fact evidence that the swap occurred.</t>
        <t>The following residuals remain and are not closed by <tt>counterparty_binding</tt> alone. The list is intentionally honest about the audit-time, not sign-time, nature of the detective evidence: a verifier resolves <tt>receipt_ref</tt> to A's retained envelope and recomputes the digest at audit time, so any residual reasoning that depends on "A is not in the loop at sign time" is rhetorical, not load-bearing.</t>
        <ul>
          <li>Collusion of M and B. If M and B are jointly compromised, M swaps the bytes in flight and B issues an acknowledging receipt carrying an <tt>envelope_hash</tt> computed over the altered bytes that B signs as if they were A's. Under <tt>counterparty_binding</tt> the audit-time verifier resolves <tt>receipt_ref</tt> to A's retained envelope and recomputes the digest, so the binding is reported non-conformant when A's storage is honest and reachable; M+B collusion alone does NOT silently succeed. M+B collusion silently succeeds only when the collusion ALSO extends to corrupting A's retained envelope, suppressing A's chain segment, or making A's storage unreachable to the auditor; that is, the true residual is M+B+(A's-storage compromise or unavailability). Operator mitigation: anchor A's chain on independent witnesses (combined <xref target="RFC3161"/> + <xref target="OPENTIMESTAMPS"/> anchors per <xref target="anchoring"/>, and OPTIONAL deployer-operated transparency logs) so that A's anchored chain-segment digests are independently recoverable from public evidence; regulator-side comparison of A's anchored chain against B's stored chain detects the divergence even when A's local storage is impeached.</li>
          <li>Collusion of M and A. If M and A are jointly compromised, A signs a fabricated envelope at M's direction and M relays it to B; B verifies M's relay normally, B's <tt>counterparty_binding</tt> correctly digests the bytes A signed, A's per-agent chain validates, and B's per-agent chain validates. Every cryptographic invariant in this profile holds because the binding correctly attests that the bytes B received were the bytes A signed; the fraud is in A's intent, not in any byte mismatch. This residual is fundamentally outside the receipt model's threat surface: no application-layer cryptographic primitive in this profile distinguishes a fraudulent A-signed envelope from an honest A-signed envelope when M is also colluding to corroborate plausibility (relay logs, timestamping, message ordering). Operator mitigation: separation of duties between issuer (A) and intermediary (M) so that the same operator cannot control both signing keys and relay logs; anchor evidence on independent witnesses under different trust roots so that an attacker controlling A and M still cannot retroactively coordinate anchor inclusion across uncolluding timestamping authorities; out-of-band attestation by the regulator or auditor of A's operational context (provenance, code signing, runtime attestation) where the policy regime authorises it.</li>
          <li>Compromise of B itself. A B that has been compromised (private key extraction, supply-chain compromise, or insider operation) can sign any <tt>envelope_hash</tt> the attacker chooses; <tt>counterparty_binding</tt> proves only that the signing key acknowledged some bytes, not that those bytes match what an honest B would have observed.</li>
          <li>Loss of A's stored envelope. <tt>counterparty_binding</tt> requires the verifier to resolve <tt>receipt_ref</tt> to A's full signed envelope; if A's chain segment is unavailable (retention discipline failure, key rotation orphan, deliberate withholding), the binding becomes unverifiable and the receipt is reported non-conformant on liveness grounds rather than on byte-equality grounds. An adversary who can arrange A-envelope unavailability and then re-emit colluding bytes can degrade the binding from a byte-equality check to a liveness-loss flag.</li>
        </ul>
        <t>Operators concerned about these residuals in the absence of single-point cryptographic defence SHOULD:</t>
        <ul>
          <li>Anchor receipts to multiple independent witnesses. Where both <xref target="RFC3161"/> and <xref target="OPENTIMESTAMPS"/> anchors are present per <xref target="anchoring"/>, a coordinated M-B collusion attack must also induce both timestamping authorities to anchor the colluding bytes within the operator's anchor interval, raising the conjunction-cost of the attack. Operators MAY add further anchors (e.g. a Deployer-operated transparency log or a witness service) without changing the wire format defined here.</li>
          <li>Use side-by-side chain comparison under regulator subpoena. The audit-trail alternative semantics established for SEC 17a-4 recordkeeping (see <xref target="sec-17a-4-f"/>) and the post-market surveillance regime of EU AI Act Articles 12 and 26 (see <xref target="article-12"/> and <xref target="article-26"/>) authorise the regulator to compel both A's and B's Audit Packs and to reconstruct the relay by joining on <tt>action_ref</tt> per <xref target="action-ref"/>. <tt>counterparty_binding</tt> reduces the regulator's workload from "compare both chains and detect divergence" to "verify B's bound digest against A's stored envelope"; the underlying subpoena-and-compare workflow remains the regulator's ultimate authority and remains operative when the binding is unverifiable.</li>
          <li>Document M's relay logs out-of-band. Where the intermediary M is identifiable (a named MCP server, message bus, orchestrator, or relay), the operator SHOULD require M to produce signed relay logs covering the time window of the Action and SHOULD submit those logs to the same Audit Pack production layer as A's and B's chains. Out-of-band relay logs do not require a wire-format change in this profile; they are operational evidence that complements <tt>counterparty_binding</tt> rather than replacing it.</li>
        </ul>
        <t>The worst-case latency to detection for an M-only compromise (not M-B collusion) is bounded by the anchor interval recommended in <xref target="tamper"/>: 24 hours by default, one hour for Deployers operating under <xref target="DORA"/> Article 17, 23 NYCRR 500.17, or <xref target="CIRCIA"/>. After the next anchor commits, the divergence between A's anchored chain segment and the digest carried in B's <tt>counterparty_binding</tt> is permanently recoverable from the anchored evidence alone, without trust in M.</t>
      </section>
    </section>

    <section anchor="iana"><name>IANA Considerations</name>
      <t>This document requests two new IANA registries to support stable, machine-checkable extensions to the Compliance Receipt format.</t>

      <section anchor="iana-extension-fields"><name>Compliance Receipt Extension Fields Registry</name>
        <t>IANA is requested to create a new registry titled "Compliance Receipt Extension Fields" under a new "Compliance Receipts" registry group.</t>
        <t>This registry covers both signed-payload fields and envelope-level fields (siblings of <tt>payload</tt> and <tt>signature</tt>); each entry's Description identifies which.</t>
        <t>Each entry contains:</t>
        <ul>
          <li>Field Name: a JSON object key, lowercase ASCII letters, digits, and underscore.</li>
          <li>Description: a one-line summary of the field's purpose.</li>
          <li>Reference: the document that defines the field's semantics.</li>
          <li>Vocabulary: a URL or registry pointer for the controlled vocabulary that field values are drawn from, or "free-form" if none.</li>
        </ul>
        <t>The registration policy is Specification Required, per <xref target="RFC8126"/>. The Designated Expert(s) SHOULD verify that the field name does not collide with any field defined by <xref target="ACTA-RECEIPTS"/>, that the Reference is a stable, dereferenceable specification, and that the Vocabulary is documented sufficiently for an independent verifier to validate values.</t>
        <t>Initial registry contents (each entry labelled with Scope to disambiguate signed-payload fields from envelope-level fields per the registry description above):</t>
        <ul>
          <li><tt>risk_class</tt> - Scope: signed-payload - Risk classification term under the Deployer's risk management documentation - This document - Vocabulary referenced in Audit Pack metadata.</li>
          <li><tt>incident_class</tt> - Scope: signed-payload - Incident classification term spanning DORA Article 18(1) (with further specification in <xref target="REG-2024-1772"/> and the canonical reporting enumeration of Annex II field 3.23 of <xref target="REG-2025-302"/>), 23 NYCRR 500.1 Cybersecurity Event/Incident, <xref target="CIRCIA"/> Covered Cyber Incident, and HIPAA security incident under 45 CFR 164.304 - This document - Audit Pack metadata.</li>
          <li><tt>counterparty_binding</tt> - Scope: signed-payload - Signed-payload object carrying a base64-encoded SHA-256 digest (<tt>envelope_hash</tt>) of a peer agent's full signed envelope including signature bytes, a resolvable opaque locator (<tt>receipt_ref</tt>), an OPTIONAL expected-acknowledger identifier (<tt>expect_ack_from</tt>), and an OPTIONAL operational <tt>transport_label</tt>; see <xref target="counterparty-binding"/> for the full member set and the digest-scope rule - This document - Member vocabulary defined in <xref target="counterparty-binding-wire"/>; digest algorithm is SHA-256 per <xref target="ACTA-RECEIPTS"/> with base64 encoding per <xref target="RFC4648"/>.</li>
          <li><tt>result_digest</tt> - Scope: signed-payload - Object of the upstream <tt>payload_digest</tt> shape (<tt>hash</tt>, <tt>size</tt>, OPTIONAL <tt>preview</tt>) carrying a SHA-256 digest of the downstream Action's result body; defined in <xref target="result-bound"/> - This document - Digest algorithm is SHA-256 with hex encoding under the <tt>sha256:&lt;64 hex&gt;</tt> form.</li>
          <li><tt>expires_at</tt> - Scope: signed-payload - ISO 8601 timestamp with explicit timezone declaring the wall-clock time after which the decision result is stale and not safe to replay; defined in <xref target="result-bound"/> - This document - Free-form ISO 8601 string.</li>
          <li><tt>nonce</tt> - Scope: signed-payload - Producer-generated string unique across the producer's emission stream for the lifetime of <tt>kid</tt>; defined in <xref target="result-bound"/> - This document - Free-form (base64url-encoded random value of at least 16 bytes, or a structured identifier such as UUIDv4, UUIDv7, ULID).</li>
          <li><tt>tool_fingerprint</tt> - Scope: signed-payload - JSON string formatted <tt>sha256:&lt;64 hex&gt;</tt> over the JCS-canonical declaration of the tool that produced the Action; defined in <xref target="result-bound"/> - This document - Digest algorithm is SHA-256 per <xref target="RFC8785"/> canonicalization.</li>
          <li><tt>config_manifest_digest</tt> - Scope: signed-payload - JSON string formatted <tt>sha256:&lt;64 hex&gt;</tt> over the canonical bytes of the producer's configuration manifest in effect at signing time; defined in <xref target="result-bound"/> - This document - Manifest content is operator-defined; canonicalization rule is operator-declared in the Audit Pack manifest entry.</li>
          <li><tt>cve_inventory_digest</tt> - Scope: signed-payload - JSON string formatted <tt>sha256:&lt;64 hex&gt;</tt> over the canonical bytes of the producer's CVE inventory at signing time; defined in <xref target="result-bound"/> - This document - Inventory content lists CVE identifiers per the producer's accepted-residual rationale.</li>
          <li><tt>executable_hash</tt> - Scope: signed-payload - JSON string formatted <tt>sha256:&lt;64 hex&gt;</tt> over the canonical bytes of the executable that invoked the Action (OCI image manifest digest for container producers, on-disk SHA-256 for non-container executables); defined in <xref target="build-provenance"/> - This document - Digest algorithm is SHA-256.</li>
          <li><tt>sbom_digest</tt> - Scope: signed-payload - JSON string formatted <tt>sha256:&lt;64 hex&gt;</tt> over the canonical bytes of the CycloneDX or SPDX SBOM document covering the executing image; defined in <xref target="build-provenance"/> - This document - SBOM format and version declared in the Audit Pack manifest entry.</li>
          <li><tt>slsa_provenance_pointer</tt> - Scope: signed-payload - JSON string carrying an https URL resolving to the SLSA provenance attestation envelope for the build of the executable identified by <tt>executable_hash</tt>; defined in <xref target="build-provenance"/> - This document - Target SHOULD be SLSA Provenance v1.0 in-toto statement form.</li>
          <li><tt>supply_chain_pointer</tt> - Scope: signed-payload - JSON string carrying an https URL resolving to a transparency-log entry (in-toto, Sigstore, or Rekor) covering the build of the executable identified by <tt>executable_hash</tt>; defined in <xref target="build-provenance"/> - This document - Verifier acceptance is SHOULD across the three log formats.</li>
          <li><tt>anchors</tt> - Scope: envelope-level - Envelope-level array of timestamp / transparency-log anchors covering the signed envelope; entries carry a REQUIRED <tt>type</tt> discriminator (<tt>rfc3161</tt> or <tt>opentimestamps</tt>) and a REQUIRED <tt>value</tt> field, plus OPTIONAL informational members <tt>status</tt> (<tt>anchored</tt> / <tt>pending</tt> / <tt>failed</tt>) and <tt>bitcoin_block</tt> (string Bitcoin block hash for upgraded OpenTimestamps entries); full schema is defined in <xref target="anchoring"/> - This document - Anchor type vocabulary: <tt>rfc3161</tt> per <xref target="RFC3161"/>, <tt>opentimestamps</tt> per <xref target="OPENTIMESTAMPS"/>.</li>
          <li><tt>witness_policy</tt> - Scope: envelope-level - Envelope-level object declaring an N-of-M durable-anchoring quorum over the <tt>anchors</tt> array; carries a REQUIRED integer <tt>required</tt> in the closed range [1, length of <tt>witnesses</tt>] and a REQUIRED non-empty array <tt>witnesses</tt> whose distinct values are a subset of {<tt>rfc3161</tt>, <tt>opentimestamps</tt>} (Rekor and other transparency-log pointers are NOT witness types and MUST be rejected). The receipt reaches the quorum-met state only when at least <tt>required</tt> distinct witness types each hold a verifiable inclusion proof; a producer MUST NOT assert durable anchoring unless that holds, per the false-attestation rule of <xref target="anchoring"/> - This document - Witness type vocabulary: <tt>rfc3161</tt> per <xref target="RFC3161"/>, <tt>opentimestamps</tt> per <xref target="OPENTIMESTAMPS"/>; inclusion-proof prior art per <xref target="DRAFT-IETF-SCITT"/> and <xref target="RFC6962"/>.</li>
          <li><tt>mitre_techniques</tt> - Scope: signed-payload - JSON array of MITRE ATT&amp;CK technique identifiers (for example <tt>T1059</tt>, <tt>T1078</tt>) self-declared by the producer; not verifier-checked by the issuing platform; flips <tt>framework_mappings_self_declared</tt> to <tt>true</tt> when populated; defined in <xref target="threat-framework"/> - This document - Vocabulary referenced by id from the MITRE ATT&amp;CK enterprise matrix.</li>
          <li><tt>mitre_atlas</tt> - Scope: signed-payload - JSON array of MITRE ATLAS identifiers (for example <tt>AML.T0051</tt>) covering AI-system-specific adversary techniques; self-declared; flips <tt>framework_mappings_self_declared</tt> to <tt>true</tt> when populated; defined in <xref target="threat-framework"/> - This document - Vocabulary referenced by id from the MITRE ATLAS catalogue.</li>
          <li><tt>owasp_llm_top10</tt> - Scope: signed-payload - JSON array of OWASP Top 10 for LLM Applications identifiers (for example <tt>LLM01</tt>, <tt>LLM02</tt>); self-declared; flips <tt>framework_mappings_self_declared</tt> to <tt>true</tt> when populated; defined in <xref target="threat-framework"/> - This document - Vocabulary referenced by id from the OWASP Top 10 for LLM Applications publication.</li>
          <li><tt>nist_ai_rmf</tt> - Scope: signed-payload - JSON array of NIST AI Risk Management Framework function identifiers and subcategories (for example <tt>GOVERN-1.1</tt>, <tt>MEASURE-2.7</tt>); self-declared; flips <tt>framework_mappings_self_declared</tt> to <tt>true</tt> when populated; defined in <xref target="threat-framework"/> - This document - Vocabulary referenced from NIST AI RMF 1.0.</li>
          <li><tt>iso_42001</tt> - Scope: signed-payload - JSON array of ISO/IEC 42001:2023 control identifiers (for example <tt>A.6.2.6</tt>); self-declared; flips <tt>framework_mappings_self_declared</tt> to <tt>true</tt> when populated; defined in <xref target="threat-framework"/> - This document - Vocabulary referenced from ISO/IEC 42001:2023.</li>
          <li><tt>eu_ai_act_articles</tt> - Scope: signed-payload - JSON array of EU AI Act article identifiers (for example <tt>Article-12</tt>, <tt>Article-15</tt>); self-declared; flips <tt>framework_mappings_self_declared</tt> to <tt>true</tt> when populated; defined in <xref target="threat-framework"/> - This document - Vocabulary referenced from <xref target="EU-AI-ACT"/>.</li>
          <li><tt>rfc3161_timestamp</tt> - Scope: signed-payload - JSON string carrying a base64-encoded RFC 3161 TimeStampResp (DER) supplied by the producer at signing time and preserved verbatim on the receipt for offline TSA chain verification independent of any platform-issued anchors; payload entry is an opaque caller-supplied token, not the per-receipt anchor produced by the platform; defined in <xref target="threat-framework"/> - This document - Bytes are an RFC 3161 TimeStampResp per <xref target="RFC3161"/>; base64 encoding per <xref target="RFC4648"/>.</li>
          <li><tt>framework_mappings_self_declared</tt> - Scope: signed-payload - JSON boolean false-attestation guard set by the issuing platform to <tt>true</tt> whenever any of <tt>mitre_techniques</tt>, <tt>mitre_atlas</tt>, <tt>owasp_llm_top10</tt>, <tt>nist_ai_rmf</tt>, <tt>iso_42001</tt>, or <tt>eu_ai_act_articles</tt> is populated; a producer-supplied value of <tt>false</tt> alongside a populated taxonomy field MUST be overridden by the issuing platform; defined in <xref target="threat-framework"/> - This document - Boolean.</li>
          <li><tt>authorized_under_mandate</tt> - Scope: signed-payload - Server-built object recording a self-declared authorizing mandate the Action was signed under; carries REQUIRED <tt>mandate_id</tt>, REQUIRED <tt>issuer_id</tt>, a REQUIRED <tt>scope_digest</tt> formatted <tt>sha256:&lt;64 hex&gt;</tt> over the mandate's authorized-action-types scope, and a REQUIRED <tt>verified</tt> boolean whose <tt>true</tt> value asserts self-declared issuer authority (the same trust level as <tt>framework_mappings_self_declared</tt>, never issuing-platform-verified third-party authorization); a present-but-malformed object is rejected by the false-attestation guard at signing time; defined in <xref target="enforcement-attestation"/> - This document - Member vocabulary defined in <xref target="enforcement-attestation"/>; <tt>scope_digest</tt> digest algorithm is SHA-256.</li>
          <li><tt>controls_evaluated</tt> - Scope: signed-payload - Server-built object enumerating the enforcement controls that genuinely fired on this sign plus the allow result; member keys are a closed set (<tt>emergency_halt</tt>, <tt>delegation_scope</tt>, <tt>quorum</tt>, <tt>mandate</tt>, <tt>policy</tt>, <tt>content_scan</tt>, <tt>result</tt>) and an unknown key is rejected; a key is present only when its control ran (omission-over-false attestation), <tt>quorum</tt> requires <tt>fired</tt>=<tt>true</tt> plus a 64-hex <tt>attestation_hash</tt>, and a <tt>policy</tt> member asserting evaluation requires <tt>matched_count</tt> at least 1; a caller-supplied value is dropped before signing; defined in <xref target="enforcement-attestation"/> - This document - Control-key vocabulary defined in <xref target="enforcement-attestation"/>.</li>
        </ul>
        <t>This document additionally requests that IANA register <tt>counterparty_binding</tt> as a new claim in the CBOR Web Token (CWT) Claims registry established by <xref target="RFC8392"/>, with this document as the reference and the semantics defined in <xref target="counterparty-binding"/>. The requested CWT claim key is TBD by IANA; this document proposes allocation from the IANA First Come First Served range (claim keys greater than or equal to -65536 and less than -256, or greater than or equal to 65536, per <xref target="RFC8392"/> Section 9.1) so as not to consume Expert Review or Standards Action space. The JSON-form claim name is the literal string <tt>counterparty_binding</tt> as registered above in the Compliance Receipt Extension Fields Registry.</t>
      </section>

      <section anchor="iana-type-namespaces"><name>Compliance Receipt Type Namespaces Registry</name>
        <t>IANA is requested to create a new registry titled "Compliance Receipt Type Namespaces" under the same "Compliance Receipts" registry group.</t>
        <t>Each entry contains:</t>
        <ul>
          <li>Namespace: a colon-separated identifier prefix used as a value of the <tt>type</tt> field, lowercase ASCII letters, digits, hyphen, underscore, and colon.</li>
          <li>Description: a one-line summary of the receipt category.</li>
          <li>Reference: the document that defines the namespace.</li>
        </ul>
        <t>The registration policy is Specification Required, per <xref target="RFC8126"/>. The Designated Expert(s) SHOULD verify that the namespace does not collide with any namespace already registered or any namespace reserved by <xref target="ACTA-RECEIPTS"/>, and that the Reference is a stable specification.</t>
        <t>Initial registry contents:</t>
        <ul>
          <li><tt>protectmcp:acknowledgment</tt> - A receipt emitted by the B-party in a <tt>counterparty_binding</tt> pair, confirming receipt of the A-party action and carrying a digest of the bound envelope per <xref target="counterparty-binding"/> - This document.</li>
          <li><tt>protectmcp:decision</tt> - A receipt recording a policy evaluation outcome (<tt>allow</tt>, <tt>deny</tt>, <tt>rate_limit</tt>) for an MCP-mediated tool call where a policy was actually evaluated; <tt>observation</tt> is reserved to <tt>protectmcp:lifecycle</tt> and <tt>protectmcp:observation</tt> per <xref target="decision-fields"/> - This document.</li>
          <li><tt>protectmcp:restraint</tt> - A receipt recording the application or release of a restraint on an agent (e.g., quota, rate limit, sandbox tightening) - This document.</li>
          <li><tt>protectmcp:lifecycle</tt> - A receipt recording an agent or system lifecycle event (e.g., configuration change, key rotation, oversight review, or a <tt>decision</tt>=<tt>observation</tt> record indicating an Action was signed without policy evaluation per <xref target="decision-fields"/>) - This document.</li>
          <li><tt>protectmcp:lifecycle:configuration_change</tt> - A receipt recording a configuration change to an agent or producing system, including changes that disable or re-enable receipt generation (see <xref target="art12-1"/>); a registered sub-namespace under <tt>protectmcp:lifecycle</tt> that the reference cloud implementation emits today - This document.</li>
          <li><tt>protectmcp:observation</tt> - A receipt recording passive telemetry about an Action that was signed without a policy evaluation, emitted under one of the capture topologies catalogued in <xref target="capture-topologies"/> (typically <tt>network_proxy</tt>, <tt>browser_extension</tt>, <tt>ebpf_observer</tt>, or <tt>mcp_proxy</tt>) where the originating application could not call the receipt-emitting SDK directly - This document.</li>
          <li><tt>protectmcp:observation:result_bound</tt> - A sub-namespace under <tt>protectmcp:observation</tt> for a follow-up observation receipt that carries a <tt>result_digest</tt> (<xref target="result-bound"/>) binding the byte-equality of a downstream Action's result to the originating <tt>protectmcp:decision</tt> receipt identified by <tt>action_ref</tt>; the reference cloud implementation emits this type for tool calls whose downstream result is regulator-relevant (LLM completions under EU AI Act Article 12, audit-log entries under HIPAA 164.312(b), broker-dealer communications under SEC 17a-4) - This document.</li>
        </ul>
      </section>
    </section>

    <section anchor="related-work"><name>Related Work</name>
      <t>This section catalogues parallel proposals that overlap the problem space of signed records for AI-agent actions. The intent is to position this profile within the broader Independent Submissions and individual drafts landscape so that an implementer can choose the surface that matches the trust model and the regulator that the implementer is bound by. The citations follow the RFC 7322 form and are informative; this section places no normative constraint on a Compliance Receipt implementation.</t>
      <ul>
        <li><xref target="DRAFT-SHARIF-APKI"/> defines a certificate-based Public Key Infrastructure for autonomous AI agents, with X.509 certificate profiles, naming conventions, and revocation considerations. Its scope is identity issuance and trust-root anchoring for agent principals; it does not define a per-action receipt format. This profile is complementary to <xref target="DRAFT-SHARIF-APKI"/>: an implementer that anchors agent identity through APKI can express the resulting <tt>kid</tt> and <tt>issuer_id</tt> values in Compliance Receipts under <xref target="issuer-id"/>, with the trust-anchor metadata of the Audit Pack resolving through the APKI certificate chain.</li>
        <li><xref target="DRAFT-SHARIF-AML"/> defines cryptographic attestation across the AI model lifecycle, from training-data provenance to inference-time output binding. Its scope is the model-build and model-evaluation surface, addressing what evidence a model producer or model consumer SHOULD retain about the model's lineage and behaviour. This profile is complementary at the per-action layer: a Deployer that consumes a model whose lifecycle attestations are produced under <xref target="DRAFT-SHARIF-AML"/> can reference those attestation digests in Compliance Receipts via <tt>config_manifest_digest</tt> (<xref target="result-bound"/>) or via the build-provenance four-tuple of <xref target="build-provenance"/> where the model is delivered as a containerized executable.</li>
        <li><xref target="PIPELOCK-ER2"/> proposes an alternative receipt format for AI agent actions under the EvidenceReceipt v2 schema. The Pipelock format is published as a public reference outside the IETF process and addresses overlapping evidence-class requirements with a different envelope, a different canonicalization choice, and a different anchoring posture. This profile and the Pipelock format are bidding for the same regulator audience under different design tradeoffs; an implementer that already deploys EvidenceReceipt v2 receipts can map the field set across the two surfaces, though byte-equality across the formats is not preserved (the canonicalization rules differ) and a cross-format verifier would have to recompute digests under each format's rule.</li>
        <li><xref target="DRAFT-IETF-SCITT"/> defines the Supply Chain Integrity, Transparency, and Trust architecture: an append-only Transparency Service that admits signed statements about an artefact and returns a receipt proving inclusion in the log, with verification reducing to a Merkle inclusion proof in the tradition of <xref target="RFC6962"/> Certificate Transparency. SCITT and RFC 6962 are the canonical inclusion-proof prior art that this profile's <tt>witness_policy</tt> (<xref target="anchoring"/>) generalizes from a single log to an N-of-M quorum over heterogeneous durable-anchoring witnesses. This profile is complementary to SCITT rather than competitive with it: a SCITT Transparent Statement MAY carry a Compliance Receipt as its signed payload, so that a Deployer operating a SCITT Transparency Service obtains a SCITT receipt whose inclusion proof can be named as one witness in a Compliance Receipt's <tt>witness_policy</tt>, while the Compliance Receipt continues to carry the regulator-facing field bindings that SCITT's artefact-neutral envelope does not define. This closes the append-only-log gap deferred under <xref target="compromised-intermediary"/>.</li>
        <li><xref target="A2A"/> defines the Agent2Agent protocol, a vendor-neutral horizontal protocol for communication between independent agents, hosted as a Linux Foundation project. A2A defines an Agent Card, an extension mechanism (data-only, profile, method, and state-machine extension classes declared inside the Agent Card capabilities and activated by clients through a request header), and an Agent Card signature that carries a detached JSON Web Signature over the Agent Card document itself. A2A is complementary to this profile rather than competitive with it: A2A's Agent Card signature attests the integrity of the card, not the execution of a per-action authorization decision, and A2A is explicitly method-agnostic on identity verification. A Deployer can reference a Compliance Receipt from an A2A Agent Card through a verifier-issued attestation pointer (a resolvable URL, a content hash over the referenced receipt, and the verifier identity expressed as a decentralized identifier), so that the Compliance Receipt's <tt>issuer_id</tt> (<xref target="issuer-id"/>) is the receipt subject and the per-action regulator-facing bindings of Sections 5 and 6 compose on top of A2A's identity layer without either layer redefining the other.</li>
        <li><xref target="A2A-IDF"/> is the Agent Identity Verification and Trust Framework proposal under the A2A protocol's contribution process, defining tiered identity verification levels (self-asserted, domain-verified, organization-verified), Agent Card signing for production agents, revocation endpoints, delegation-chain verification, and per-message signing. Its scope is the identity and trust-anchoring layer beneath per-action receipts; it does not define a regulator-facing per-action receipt format, and its post-quantum cryptography work is scheduled for a later cycle. This profile is complementary to <xref target="A2A-IDF"/> at the per-action layer: an implementer that anchors agent identity through an A2A-IDF verification level can express the resulting identity as the <tt>issuer_id</tt> and <tt>kid</tt> of Compliance Receipts under <xref target="issuer-id"/>, while this profile already signs receipts with the ML-DSA-65 post-quantum signature algorithm of <xref target="FIPS204"/> that the surrounding agent-identity ecosystem largely defers.</li>
        <li><xref target="DRAFT-HOPLEY-X402"/> is the closest parallel receipt format: it defines a Compliance Receipt minted at admission time under a payment-gate remote procedure call, carrying an ALLOW, REFER, or DENY verdict bound to a payment mandate. The format canonicalizes under <xref target="RFC8785"/> JCS, digests under SHA-256, and links receipts in a monotonic hash chain (position plus content hash plus previous-hash), in the same family of design primitives as this profile (JCS canonicalization, SHA-256 digests, hash-chain linkage under <xref target="hash-chain"/>, and a categorical decision under <xref target="decision-fields"/> bound to an authorizing mandate under <xref target="enforcement-attestation"/>). The two drafts differ in scope and trust model. <xref target="DRAFT-HOPLEY-X402"/> is narrowed to payment anti-money-laundering and sanctions-screening admission decisions, is bound to a payment-settlement substrate, and its REFER verdict carries a jurisdiction-specific suspicious-activity-reporting meaning. This profile is the broader superset: it covers general agent-action receipts across regulatory regimes rather than payment screening alone (Sections 5 and 6), it is signed by a neutral third party rather than by the screening party itself (the unaffiliated-custodian posture the recordkeeping bindings of Sections 5 and 6 anchor), it carries the organization-wide enforcement controls enumerated in <tt>controls_evaluated</tt> (<xref target="enforcement-attestation"/>) rather than a single admission verdict, and it signs with the ML-DSA-65 post-quantum algorithm of <xref target="FIPS204"/>. An implementer deploying both can map the verdict and mandate-binding fields across the two surfaces, though byte-equality is not preserved because the envelope shapes differ.</li>
      </ul>
      <t>This section is non-exhaustive. The Independent Submissions stream and the individual-draft search surface of the IETF Datatracker host additional proposals whose scope intersects the Compliance Receipt problem space; an implementer evaluating the field is encouraged to re-query the Datatracker against the keywords "agent", "receipt", "attestation", and "audit trail" at the time of implementation. The author welcomes pull requests against the source repository of this draft naming additional active parallel work.</t>
    </section>

    <section anchor="acks"><name>Acknowledgements</name>
      <t>The author thanks Tom Farley for <xref target="ACTA-RECEIPTS"/>, on which this profile is built. This profile would not exist without the field catalogue and envelope structure that the upstream draft defines. The author also thanks the Asqav community for review of early drafts.</t>
    </section>
  </middle>

  <back>
    <references>
      <name>Normative References</name>
      <reference anchor="RFC2119" target="https://www.rfc-editor.org/info/rfc2119">
        <front>
          <title>Key words for use in RFCs to Indicate Requirement Levels</title>
          <author fullname="S. Bradner" initials="S." surname="Bradner"/>
          <date year="1997" month="March"/>
        </front>
        <seriesInfo name="BCP" value="14"/>
        <seriesInfo name="RFC" value="2119"/>
        <seriesInfo name="DOI" value="10.17487/RFC2119"/>
      </reference>
      <reference anchor="RFC8174" target="https://www.rfc-editor.org/info/rfc8174">
        <front>
          <title>Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words</title>
          <author fullname="B. Leiba" initials="B." surname="Leiba"/>
          <date year="2017" month="May"/>
        </front>
        <seriesInfo name="BCP" value="14"/>
        <seriesInfo name="RFC" value="8174"/>
        <seriesInfo name="DOI" value="10.17487/RFC8174"/>
      </reference>
      <reference anchor="RFC8032" target="https://www.rfc-editor.org/info/rfc8032">
        <front>
          <title>Edwards-Curve Digital Signature Algorithm (EdDSA)</title>
          <author fullname="S. Josefsson" initials="S." surname="Josefsson"/>
          <author fullname="I. Liusvaara" initials="I." surname="Liusvaara"/>
          <date year="2017" month="January"/>
        </front>
        <seriesInfo name="RFC" value="8032"/>
        <seriesInfo name="DOI" value="10.17487/RFC8032"/>
      </reference>
      <reference anchor="RFC7518" target="https://www.rfc-editor.org/info/rfc7518">
        <front>
          <title>JSON Web Algorithms (JWA)</title>
          <author fullname="M. Jones" initials="M." surname="Jones"/>
          <date year="2015" month="May"/>
        </front>
        <seriesInfo name="RFC" value="7518"/>
        <seriesInfo name="DOI" value="10.17487/RFC7518"/>
      </reference>
      <reference anchor="FIPS204" target="https://csrc.nist.gov/pubs/fips/204/final">
        <front>
          <title>Module-Lattice-Based Digital Signature Standard</title>
          <author><organization>National Institute of Standards and Technology</organization></author>
          <date year="2024" month="August" day="13"/>
        </front>
        <seriesInfo name="FIPS" value="204"/>
        <seriesInfo name="DOI" value="10.6028/NIST.FIPS.204"/>
      </reference>
      <reference anchor="RFC5816" target="https://www.rfc-editor.org/info/rfc5816">
        <front>
          <title>ESSCertIDv2 Update for RFC 3161</title>
          <author fullname="S. Santesson" initials="S." surname="Santesson"/>
          <author fullname="N. Pope" initials="N." surname="Pope"/>
          <date year="2010" month="April"/>
        </front>
        <seriesInfo name="RFC" value="5816"/>
        <seriesInfo name="DOI" value="10.17487/RFC5816"/>
      </reference>
      <reference anchor="RFC3161" target="https://www.rfc-editor.org/info/rfc3161">
        <front>
          <title>Internet X.509 Public Key Infrastructure Time-Stamp Protocol (TSP)</title>
          <author fullname="C. Adams" initials="C." surname="Adams"/>
          <author fullname="P. Cain" initials="P." surname="Cain"/>
          <author fullname="D. Pinkas" initials="D." surname="Pinkas"/>
          <author fullname="R. Zuccherato" initials="R." surname="Zuccherato"/>
          <date year="2001" month="August"/>
        </front>
        <seriesInfo name="RFC" value="3161"/>
        <seriesInfo name="DOI" value="10.17487/RFC3161"/>
      </reference>
      <reference anchor="RFC8126" target="https://www.rfc-editor.org/info/rfc8126">
        <front>
          <title>Guidelines for Writing an IANA Considerations Section in RFCs</title>
          <author fullname="M. Cotton" initials="M." surname="Cotton"/>
          <author fullname="B. Leiba" initials="B." surname="Leiba"/>
          <author fullname="T. Narten" initials="T." surname="Narten"/>
          <date year="2017" month="June"/>
        </front>
        <seriesInfo name="BCP" value="26"/>
        <seriesInfo name="RFC" value="8126"/>
        <seriesInfo name="DOI" value="10.17487/RFC8126"/>
      </reference>
      <reference anchor="OPENTIMESTAMPS" target="https://github.com/opentimestamps/opentimestamps-server">
        <front>
          <title>OpenTimestamps Server</title>
          <author>
            <organization>OpenTimestamps</organization>
          </author>
          <date year="2016" month="September"/>
        </front>
      </reference>
      <reference anchor="ACTA-RECEIPTS" target="https://datatracker.ietf.org/doc/html/draft-farley-acta-signed-receipts-01">
        <front>
          <title>Signed Decision Receipts for Machine-to-Machine Access Control</title>
          <author fullname="Tom Farley" initials="T." surname="Farley"/>
          <date year="2026" month="April" day="25"/>
        </front>
        <seriesInfo name="Internet-Draft" value="draft-farley-acta-signed-receipts-01"/>
      </reference>
      <reference anchor="RFC8785" target="https://www.rfc-editor.org/info/rfc8785">
        <front>
          <title>JSON Canonicalization Scheme (JCS)</title>
          <author fullname="A. Rundgren" initials="A." surname="Rundgren"/>
          <author fullname="B. Jordan" initials="B." surname="Jordan"/>
          <author fullname="S. Erdtman" initials="S." surname="Erdtman"/>
          <date year="2020" month="June"/>
        </front>
        <seriesInfo name="RFC" value="8785"/>
        <seriesInfo name="DOI" value="10.17487/RFC8785"/>
      </reference>
      <!-- ISO source title uses em-dashes (U+2014); replaced with ASCII hyphens per profile style. -->
      <reference anchor="ISO17442" target="https://www.iso.org/standard/78829.html">
        <front>
          <title>Financial services - Legal entity identifier (LEI) - Part 1: Assignment</title>
          <author><organization>ISO</organization></author>
          <date year="2020" month="August"/>
        </front>
        <seriesInfo name="ISO" value="17442-1:2020"/>
      </reference>
      <reference anchor="W3C-DID" target="https://www.w3.org/TR/did-1.0/">
        <front>
          <title>Decentralized Identifiers (DIDs) v1.0</title>
          <author><organization>W3C</organization></author>
          <date year="2022" month="July" day="19"/>
        </front>
      </reference>
      <reference anchor="RFC9052" target="https://www.rfc-editor.org/info/rfc9052">
        <front>
          <title>CBOR Object Signing and Encryption (COSE): Structures and Process</title>
          <author fullname="J. Schaad" initials="J." surname="Schaad"/>
          <date year="2022" month="August"/>
        </front>
        <seriesInfo name="STD" value="96"/>
        <seriesInfo name="RFC" value="9052"/>
        <seriesInfo name="DOI" value="10.17487/RFC9052"/>
      </reference>
      <reference anchor="RFC8949" target="https://www.rfc-editor.org/info/rfc8949">
        <front>
          <title>Concise Binary Object Representation (CBOR)</title>
          <author fullname="C. Bormann" initials="C." surname="Bormann"/>
          <author fullname="P. Hoffman" initials="P." surname="Hoffman"/>
          <date year="2020" month="December"/>
        </front>
        <seriesInfo name="STD" value="94"/>
        <seriesInfo name="RFC" value="8949"/>
        <seriesInfo name="DOI" value="10.17487/RFC8949"/>
      </reference>
      <reference anchor="RFC7515" target="https://www.rfc-editor.org/info/rfc7515">
        <front>
          <title>JSON Web Signature (JWS)</title>
          <author fullname="M. Jones" initials="M." surname="Jones"/>
          <author fullname="J. Bradley" initials="J." surname="Bradley"/>
          <author fullname="N. Sakimura" initials="N." surname="Sakimura"/>
          <date year="2015" month="May"/>
        </front>
        <seriesInfo name="RFC" value="7515"/>
        <seriesInfo name="DOI" value="10.17487/RFC7515"/>
      </reference>
      <reference anchor="RFC8392" target="https://www.rfc-editor.org/info/rfc8392">
        <front>
          <title>CBOR Web Token (CWT)</title>
          <author fullname="M. Jones" initials="M." surname="Jones"/>
          <author fullname="E. Wahlstroem" initials="E." surname="Wahlstroem"/>
          <author fullname="S. Erdtman" initials="S." surname="Erdtman"/>
          <author fullname="H. Tschofenig" initials="H." surname="Tschofenig"/>
          <date year="2018" month="May"/>
        </front>
        <seriesInfo name="RFC" value="8392"/>
        <seriesInfo name="DOI" value="10.17487/RFC8392"/>
      </reference>
      <reference anchor="RFC4648" target="https://www.rfc-editor.org/info/rfc4648">
        <front>
          <title>The Base16, Base32, and Base64 Data Encodings</title>
          <author fullname="S. Josefsson" initials="S." surname="Josefsson"/>
          <date year="2006" month="October"/>
        </front>
        <seriesInfo name="RFC" value="4648"/>
        <seriesInfo name="DOI" value="10.17487/RFC4648"/>
      </reference>
      <reference anchor="NIST-GENAI-PROFILE" target="https://nvlpubs.nist.gov/nistpubs/ai/NIST.AI.600-1.pdf">
        <front>
          <title>Artificial Intelligence Risk Management Framework: Generative Artificial Intelligence Profile</title>
          <author><organization>National Institute of Standards and Technology</organization></author>
          <date year="2024" month="July" day="26"/>
        </front>
        <seriesInfo name="NIST" value="AI 600-1"/>
        <seriesInfo name="DOI" value="10.6028/NIST.AI.600-1"/>
      </reference>
    </references>

    <references>
      <name>Informative References</name>
      <reference anchor="RFC8446" target="https://www.rfc-editor.org/info/rfc8446">
        <front>
          <title>The Transport Layer Security (TLS) Protocol Version 1.3</title>
          <author fullname="E. Rescorla" initials="E." surname="Rescorla"/>
          <date year="2018" month="August"/>
        </front>
        <seriesInfo name="RFC" value="8446"/>
        <seriesInfo name="DOI" value="10.17487/RFC8446"/>
      </reference>
      <reference anchor="RFC5705" target="https://www.rfc-editor.org/info/rfc5705">
        <front>
          <title>Keying Material Exporters for Transport Layer Security (TLS)</title>
          <author fullname="E. Rescorla" initials="E." surname="Rescorla"/>
          <date year="2010" month="March"/>
        </front>
        <seriesInfo name="RFC" value="5705"/>
        <seriesInfo name="DOI" value="10.17487/RFC5705"/>
      </reference>
      <reference anchor="RFC9266" target="https://www.rfc-editor.org/info/rfc9266">
        <front>
          <title>Channel Bindings for TLS 1.3</title>
          <author fullname="S. Whited" initials="S." surname="Whited"/>
          <date year="2022" month="July"/>
        </front>
        <seriesInfo name="RFC" value="9266"/>
        <seriesInfo name="DOI" value="10.17487/RFC9266"/>
      </reference>
      <reference anchor="RFC9421" target="https://www.rfc-editor.org/info/rfc9421">
        <front>
          <title>HTTP Message Signatures</title>
          <author fullname="A. Backman" initials="A." surname="Backman" role="editor"/>
          <author fullname="J. Richer" initials="J." surname="Richer" role="editor"/>
          <author fullname="M. Sporny" initials="M." surname="Sporny"/>
          <date year="2024" month="February"/>
        </front>
        <seriesInfo name="RFC" value="9421"/>
        <seriesInfo name="DOI" value="10.17487/RFC9421"/>
      </reference>
      <reference anchor="ISO8601-2" target="https://www.iso.org/standard/70908.html">
        <front>
          <title>Date and time - Representations for information interchange - Part 2: Extensions</title>
          <author><organization>ISO</organization></author>
          <date year="2019" month="February"/>
        </front>
        <seriesInfo name="ISO" value="8601-2:2019"/>
      </reference>
      <reference anchor="EU-AI-ACT" target="https://eur-lex.europa.eu/eli/reg/2024/1689/oj">
        <front>
          <title>Regulation (EU) 2024/1689 of the European Parliament and of the Council of 13 June 2024 laying down harmonised rules on artificial intelligence and amending Regulations (EC) No 300/2008, (EU) No 167/2013, (EU) No 168/2013, (EU) 2018/858, (EU) 2018/1139 and (EU) 2019/2144 and Directives 2014/90/EU, (EU) 2016/797 and (EU) 2020/1828 (Artificial Intelligence Act) (Text with EEA relevance)</title>
          <author>
            <organization>European Parliament and Council</organization>
          </author>
          <date year="2024" month="July" day="12"/>
        </front>
      </reference>
      <reference anchor="DORA" target="https://eur-lex.europa.eu/eli/reg/2022/2554/oj">
        <front>
          <title>Regulation (EU) 2022/2554 of the European Parliament and of the Council of 14 December 2022 on digital operational resilience for the financial sector and amending Regulations (EC) No 1060/2009, (EU) No 648/2012, (EU) No 600/2014, (EU) No 909/2014 and (EU) 2016/1011 (Text with EEA relevance)</title>
          <author>
            <organization>European Parliament and Council</organization>
          </author>
          <date year="2022" month="December" day="27"/>
        </front>
      </reference>
      <reference anchor="REG-2025-301" target="https://eur-lex.europa.eu/eli/reg_del/2025/301/oj">
        <front>
          <title>Commission Delegated Regulation (EU) 2025/301 of 23 October 2024 supplementing Regulation (EU) 2022/2554 of the European Parliament and of the Council with regard to regulatory technical standards specifying the content, timelines and templates on the reporting of major ICT-related incidents and significant cyber threats (Text with EEA relevance)</title>
          <author><organization>European Commission</organization></author>
          <date year="2025" month="February" day="20"/>
        </front>
      </reference>
      <reference anchor="REG-2025-302" target="https://eur-lex.europa.eu/eli/reg_impl/2025/302/oj">
        <front>
          <title>Commission Implementing Regulation (EU) 2025/302 of 23 October 2024 laying down implementing technical standards for the application of Regulation (EU) 2022/2554 of the European Parliament and of the Council with regard to the standard forms, templates, and procedures for financial entities to report a major ICT-related incident and to notify a significant cyber threat (Text with EEA relevance)</title>
          <author><organization>European Commission</organization></author>
          <date year="2025" month="February" day="20"/>
        </front>
      </reference>
      <reference anchor="REG-2024-1772" target="https://eur-lex.europa.eu/eli/reg_del/2024/1772/oj">
        <front>
          <title>Commission Delegated Regulation (EU) 2024/1772 of 13 March 2024 supplementing Regulation (EU) 2022/2554 of the European Parliament and of the Council with regard to regulatory technical standards specifying the criteria for the classification of ICT-related incidents and cyber threats, setting out materiality thresholds and specifying the details of reports of major incidents (Text with EEA relevance)</title>
          <author><organization>European Commission</organization></author>
          <date year="2024" month="June" day="25"/>
        </front>
      </reference>
      <reference anchor="MIFID2" target="https://eur-lex.europa.eu/eli/dir/2014/65/oj">
        <front>
          <title>Directive 2014/65/EU of the European Parliament and of the Council of 15 May 2014 on markets in financial instruments and amending Directive 2002/92/EC and Directive 2011/61/EU (recast) (Text with EEA relevance)</title>
          <author><organization>European Parliament and Council</organization></author>
          <date year="2014" month="June" day="12"/>
        </front>
      </reference>
      <reference anchor="REG-2017-565" target="https://eur-lex.europa.eu/eli/reg_del/2017/565/oj">
        <front>
          <title>Commission Delegated Regulation (EU) 2017/565 of 25 April 2016 supplementing Directive 2014/65/EU of the European Parliament and of the Council as regards organisational requirements and operating conditions for investment firms and defined terms for the purposes of that Directive (Text with EEA relevance)</title>
          <author><organization>European Commission</organization></author>
          <date year="2017" month="March" day="31"/>
        </front>
      </reference>
      <reference anchor="AMLD" target="https://eur-lex.europa.eu/eli/dir/2015/849/oj">
        <front>
          <title>Directive (EU) 2015/849 of the European Parliament and of the Council of 20 May 2015 on the prevention of the use of the financial system for the purposes of money laundering or terrorist financing, amending Regulation (EU) No 648/2012 of the European Parliament and of the Council, and repealing Directive 2005/60/EC of the European Parliament and of the Council and Commission Directive 2006/70/EC (Text with EEA relevance)</title>
          <author><organization>European Parliament and Council</organization></author>
          <date year="2015" month="June" day="5"/>
        </front>
      </reference>
      <reference anchor="AMLR" target="https://eur-lex.europa.eu/eli/reg/2024/1624/oj">
        <front>
          <title>Regulation (EU) 2024/1624 of the European Parliament and of the Council of 31 May 2024 on the prevention of the use of the financial system for the purposes of money laundering or terrorist financing (Text with EEA relevance)</title>
          <author><organization>European Parliament and Council</organization></author>
          <date year="2024" month="June" day="19"/>
        </front>
      </reference>
      <reference anchor="NIST-AI-RMF" target="https://nvlpubs.nist.gov/nistpubs/ai/NIST.AI.100-1.pdf">
        <front>
          <title>Artificial Intelligence Risk Management Framework (AI RMF 1.0)</title>
          <author><organization>National Institute of Standards and Technology</organization></author>
          <date year="2023" month="January" day="26"/>
        </front>
        <seriesInfo name="NIST" value="AI 100-1"/>
        <seriesInfo name="DOI" value="10.6028/NIST.AI.100-1"/>
      </reference>
      <reference anchor="COLORADO-AI-ACT" target="https://leg.colorado.gov/bills/sb24-205">
        <front>
          <title>Senate Bill 24-205, Consumer Protections for Artificial Intelligence</title>
          <author><organization>State of Colorado, Seventy-Fourth General Assembly</organization></author>
          <date year="2024" month="May" day="17"/>
        </front>
      </reference>
      <reference anchor="TEXAS-TRAIGA" target="https://capitol.texas.gov/BillLookup/History.aspx?LegSess=89R&amp;Bill=HB149">
        <front>
          <title>House Bill 149, Texas Responsible Artificial Intelligence Governance Act</title>
          <author><organization>State of Texas, 89th Legislature, Regular Session</organization></author>
          <date year="2025" month="June" day="22"/>
        </front>
      </reference>
      <reference anchor="HIPAA-SECURITY" target="https://www.ecfr.gov/current/title-45/subtitle-A/subchapter-C/part-164">
        <front>
          <title>HIPAA Security Rule, 45 CFR Part 164, Subpart C, Security Standards for the Protection of Electronic Protected Health Information</title>
          <author><organization>United States Department of Health and Human Services</organization></author>
          <date year="2003" month="February" day="20"/>
        </front>
      </reference>
      <reference anchor="NYDFS-500" target="https://www.dfs.ny.gov/industry-guidance/cybersecurity">
        <front>
          <title>23 NYCRR Part 500, Cybersecurity Requirements for Financial Services Companies</title>
          <author><organization>New York State Department of Financial Services</organization></author>
          <date year="2017" month="March" day="1"/>
        </front>
      </reference>
      <reference anchor="SEC-17A-4" target="https://www.federalregister.gov/documents/2022/11/03/2022-22670/electronic-recordkeeping-requirements-for-broker-dealers-security-based-swap-dealers-and-major">
        <front>
          <title>Electronic Recordkeeping Requirements for Broker-Dealers, Security-Based Swap Dealers, and Major Security-Based Swap Participants (Rule 17a-4 Amendments)</title>
          <author><organization>United States Securities and Exchange Commission</organization></author>
          <date year="2022" month="November" day="3"/>
        </front>
        <annotation>Effective date January 3, 2023; compliance date for amendments to 17 CFR 240.17a-4 May 3, 2023.</annotation>
      </reference>
      <reference anchor="CIRCIA" target="https://www.congress.gov/117/plaws/publ103/PLAW-117publ103.pdf">
        <front>
          <title>Cyber Incident Reporting for Critical Infrastructure Act of 2022, enacted as Division Y of the Consolidated Appropriations Act, 2022 (Public Law 117-103); statutory authority codified at 6 U.S.C. 681 et seq.</title>
          <author><organization>United States Congress</organization></author>
          <date year="2022" month="March" day="15"/>
        </front>
        <annotation>Public Law 117-103 was enacted on March 15, 2022. Implementing regulations are proceeding under a CISA notice of proposed rulemaking at 89 FR 23644 (April 4, 2024); the final rule is pending publication.</annotation>
      </reference>
      <reference anchor="DRAFT-SHARIF-APKI" target="https://datatracker.ietf.org/doc/draft-sharif-apki-agent-pki/">
        <front>
          <title>Agent Public Key Infrastructure (APKI): Certificate-Based Identity and Trust for Autonomous AI Agents</title>
          <author surname="Sharif"><organization>Independent</organization></author>
          <date year="2025"/>
        </front>
        <seriesInfo name="Internet-Draft" value="draft-sharif-apki-agent-pki-00"/>
        <annotation>Active Independent Submission on the IETF Datatracker; defines a certificate-based PKI for autonomous AI agents. Cited under <xref target="related-work"/> as parallel work on the identity-anchoring surface complementary to this profile's per-action receipt format.</annotation>
      </reference>
      <reference anchor="DRAFT-SHARIF-AML" target="https://datatracker.ietf.org/doc/draft-sharif-ai-model-lifecycle-attestation/">
        <front>
          <title>Cryptographic Attestation for AI Model Lifecycle: From Training Data to Inference Output</title>
          <author surname="Sharif"><organization>Independent</organization></author>
          <date year="2025"/>
        </front>
        <seriesInfo name="Internet-Draft" value="draft-sharif-ai-model-lifecycle-attestation-00"/>
        <annotation>Active Independent Submission on the IETF Datatracker; defines cryptographic attestation across the AI model lifecycle from training-data provenance to inference-time output binding. Cited under <xref target="related-work"/> as parallel work on the model-build and model-evaluation surface complementary to this profile's per-action receipt format.</annotation>
      </reference>
      <reference anchor="PIPELOCK-ER2" target="https://pipelock.ai/evidence-receipt-v2">
        <front>
          <title>EvidenceReceipt v2: An Alternative Receipt Format for AI Agent Actions</title>
          <author><organization>Pipelock</organization></author>
          <date year="2025"/>
        </front>
        <annotation>Public reference published outside the IETF process. Cited under <xref target="related-work"/> as an alternative receipt-format proposal under different envelope, canonicalization, and anchoring choices; byte-equality across the two formats is not preserved.</annotation>
      </reference>
      <reference anchor="A2A" target="https://github.com/a2aproject/A2A">
        <front>
          <title>Agent2Agent (A2A) Protocol</title>
          <author><organization>A2A Project, a Linux Foundation project</organization></author>
          <date year="2025"/>
        </front>
        <annotation>Vendor-neutral horizontal protocol for communication between independent agents, hosted as a Linux Foundation project. Defines an Agent Card, an extension mechanism, and a JSON Web Signature over the Agent Card document. Cited under <xref target="related-work"/> as parallel work on the agent-interoperation surface complementary to this profile's per-action receipt format; A2A is method-agnostic on identity verification and does not define a regulator-facing per-action receipt format.</annotation>
      </reference>
      <reference anchor="A2A-IDF" target="https://github.com/a2aproject/A2A/issues/1497">
        <front>
          <title>Agent Identity Verification and Trust Framework (A2A-IDF)</title>
          <author><organization>A2A Project contributors</organization></author>
          <date year="2026"/>
        </front>
        <annotation>Identity and trust-framework proposal under the A2A protocol contribution process, defining tiered verification levels, Agent Card signing, revocation, and delegation-chain verification. Cited under <xref target="related-work"/> as parallel work on the identity-anchoring layer beneath this profile's per-action receipts; post-quantum cryptography is scheduled for a later cycle.</annotation>
      </reference>
      <reference anchor="DRAFT-HOPLEY-X402" target="https://datatracker.ietf.org/doc/draft-hopley-x402-compliance-receipt/">
        <front>
          <title>x402 Compliance Receipt</title>
          <author fullname="Christopher Hopley" initials="C." surname="Hopley"/>
          <date year="2026" month="May" day="25"/>
        </front>
        <seriesInfo name="Internet-Draft" value="draft-hopley-x402-compliance-receipt-02"/>
        <annotation>Independent Submission, Informational. Defines a JCS-canonicalized, SHA-256 hash-chained Compliance Receipt carrying an ALLOW, REFER, or DENY admission verdict bound to a payment mandate under the x402 payment substrate. Cited under <xref target="related-work"/> as the closest parallel receipt format; this profile is the broader superset (general agent-action receipts, neutral third-party signing, organization-wide control attestation, ML-DSA-65) and that draft is narrowed to payment anti-money-laundering and sanctions-screening admission decisions.</annotation>
      </reference>
      <reference anchor="DRAFT-IETF-SCITT" target="https://datatracker.ietf.org/doc/draft-ietf-scitt-architecture/">
        <front>
          <title>An Architecture for Trustworthy and Transparent Digital Supply Chains</title>
          <author><organization>IETF SCITT Working Group</organization></author>
          <date year="2025"/>
        </front>
        <seriesInfo name="Internet-Draft" value="draft-ietf-scitt-architecture"/>
        <annotation>IETF SCITT Working Group draft defining an append-only Transparency Service that issues inclusion-proof receipts over signed statements. Cited under <xref target="related-work"/> as canonical inclusion-proof prior art complementary to this profile's <tt>witness_policy</tt>; a SCITT Transparent Statement can carry a Compliance Receipt as its payload.</annotation>
      </reference>
      <reference anchor="RFC6962" target="https://www.rfc-editor.org/info/rfc6962">
        <front>
          <title>Certificate Transparency</title>
          <author initials="B." surname="Laurie"/>
          <author initials="A." surname="Langley"/>
          <author initials="E." surname="Kasper"/>
          <date year="2013" month="June"/>
        </front>
        <seriesInfo name="RFC" value="6962"/>
        <seriesInfo name="DOI" value="10.17487/RFC6962"/>
        <annotation>Defines the Merkle-tree inclusion-proof model for an append-only public log. Cited under <xref target="related-work"/> as the foundational inclusion-proof prior art that this profile's <tt>witness_policy</tt> generalizes to an N-of-M quorum over heterogeneous durable-anchoring witnesses.</annotation>
      </reference>
    </references>

    <section anchor="example" numbered="false"><name>Worked Example (Informative)</name>
      <t>This appendix illustrates a Compliance Receipt that satisfies the EU AI Act Article 26 binding for a tool invocation by a High-Risk AI System deployed by a Financial Entity. The wire shape applies identically to United States bindings; the only differences are the values placed in <tt>issuer_id</tt> (LEI, EIN, or CIK depending on the regime) and in the <tt>risk_class</tt> and <tt>incident_class</tt> vocabularies referenced in the Audit Pack manifest. Field values are abbreviated for readability and are not cryptographically valid. The example shows a mid-chain receipt; a chain-genesis receipt would carry a <tt>previousReceiptHash</tt> of 64 zero hex characters per <xref target="hash-chain"/>.</t>
      <t>The worked example below is illustrative. The digest-valued fields (<tt>action_ref</tt>, <tt>policy_digest</tt>, the <tt>hash</tt> member of <tt>payload_digest</tt>, and <tt>previousReceiptHash</tt>) are shown abbreviated with an internal ellipsis so each line fits the column width; a real receipt carries the full 64-character lowercase hex digest. The keys are shown in human-readable order rather than JCS-canonical lexicographic order; the JCS-canonical bytes used as input to SHA-256 reorder keys lexicographically (so the on-the-wire byte order for hashing is <tt>action_ref</tt>, <tt>decision</tt>, <tt>issued_at</tt>, <tt>issuer_id</tt>, <tt>iteration_id</tt>, <tt>payload_digest</tt>, <tt>policy_digest</tt>, <tt>previousReceiptHash</tt>, <tt>reason</tt>, <tt>risk_class</tt>, <tt>sandbox_state</tt>, <tt>tool_name</tt>, <tt>type</tt>, with each nested object's keys also lexicographically sorted, per <xref target="RFC8785"/>). The <tt>sig</tt> value, the <tt>anchors</tt> <tt>value</tt> entries, and the <tt>hash</tt> hex values are deterministic placeholders chosen for shape rather than cryptographic validity. Implementations MUST NOT replay or trust this example as a real receipt; the example is not signed by any allocated <tt>issuer_id</tt>, is not anchored against any TSA or OpenTimestamps calendar, and does not chain into any retained predecessor.</t>
      <sourcecode type="json"><![CDATA[
{
  "payload": {
    "type": "protectmcp:decision",
    "issued_at": "2026-05-04T09:14:22.118Z",
    "issuer_id": "00000000000000000098",
    "action_ref": "c1f3a09a4d2e7f6b8c5a91e3d7b04f2a...3c5e7f9d",
    "tool_name": "deploy",
    "iteration_id": "task-2026-05-04-01a3",
    "decision": "allow",
    "reason": "policy:within_limits",
    "policy_digest": "sha256:7b214e8c3d9f4a2b1e6c8f5a...1f3a5d7b",
    "sandbox_state": "enabled",
    "payload_digest": {
      "hash": "0a44d2c8e3f5b7a9d1c4e6f8b2a5d7c9...e7f9b2a4",
      "size": 1024
    },
    "previousReceiptHash": "f80c11a3b5d7e9c2f4a6b8d1...b8d1e3c5",
    "risk_class": "deployer:financial:medium"
  },
  "signature": {
    "alg": "EdDSA",
    "kid": "00000000000000000098",
    "sig": "..."
  },
  "anchors": [
    {
      "type": "rfc3161",
      "value": "..."
    },
    {
      "type": "opentimestamps",
      "value": "..."
    }
  ]
}
]]></sourcecode>
      <t>The above receipt satisfies the Article 26 binding because:</t>
      <ul>
        <li><tt>issuer_id</tt> is a 20-character ISO 17442 Legal Entity Identifier (LEI) that resolves through the trust anchor metadata in the Audit Pack to the named Deployer;</li>
        <li><tt>policy_digest</tt> resolves to a retained policy artefact;</li>
        <li><tt>sandbox_state</tt> is enabled, satisfying the High-Risk system constraint of <xref target="sandbox-state"/>;</li>
        <li><tt>previousReceiptHash</tt> links the receipt into the chain per <xref target="hash-chain"/>;</li>
        <li>both an <xref target="RFC3161"/> anchor and an <xref target="OPENTIMESTAMPS"/> anchor are present per <xref target="anchoring"/>.</li>
      </ul>
      <t>Under the DORA Article 17 binding a Compliance Verifier additionally checks the longest applicable sectoral retention floor (1827 days as the default, per <xref target="dora-retention"/>) and, where present, that <tt>incident_class</tt> flattens to the canonical vocabulary referenced in <xref target="extension-fields"/> (resolved from <xref target="REG-2025-302"/> Annex II field 3.23 directly). Under the United States bindings of Section 6 the same verifier additionally checks the longest applicable retention floor (2192 days as the default for receipts under <xref target="hipaa"/> or <xref target="sec"/>) and, where the Deployer is a NYDFS Covered Entity, a HIPAA Covered Entity, or a CIRCIA Covered Entity, that <tt>incident_class</tt> resolves to the applicable canonical category for each in-scope regime.</t>
    </section>

    <section anchor="changelog" numbered="false"><name>Change Log</name>
      <t>[RFC Editor: please remove this appendix and its subsections before publication.]</t>
      <section anchor="cl-05" numbered="false"><name>Changes in draft -05</name>
        <t>Build-provenance and result-bound extension revision. This revision registers vocabulary that the reference cloud implementation, the asqav-sdk Python and TypeScript halves, and the published <tt>/.well-known/governance.json</tt> already emit and accept, bringing the IETF surface back into parity with deployed reality.</t>
        <ul>
          <li>New normative <xref target="result-bound"/> defines six OPTIONAL signed-payload extension fields: <tt>result_digest</tt> (object of the upstream <tt>payload_digest</tt> shape carrying the downstream Action's result-body SHA-256), <tt>expires_at</tt> (ISO 8601 staleness bound additive to the 300-second forward-skew rule of <xref target="issued-at"/>), <tt>nonce</tt> (producer-unique replay-resistance value), <tt>tool_fingerprint</tt> (JCS-canonicalized tool-declaration SHA-256), <tt>config_manifest_digest</tt> (operator-defined configuration manifest SHA-256), and <tt>cve_inventory_digest</tt> (CVE inventory SHA-256 in effect at signing time). The six fields are type-agnostic; <tt>result_digest</tt> typically appears on receipts of the newly registered <tt>protectmcp:observation:result_bound</tt> namespace.</li>
          <li>New normative <xref target="build-provenance"/> defines a four-tuple of OPTIONAL signed-payload extension fields binding the executing build to the receipt: <tt>executable_hash</tt> (OCI image manifest digest for container producers, on-disk SHA-256 for non-container executables), <tt>sbom_digest</tt> (CycloneDX or SPDX SBOM SHA-256), <tt>slsa_provenance_pointer</tt> (https URL to the SLSA Provenance v1.0 in-toto attestation envelope), and <tt>supply_chain_pointer</tt> (https URL to an in-toto, Sigstore, or Rekor transparency-log entry covering the build). The four fields form a layered subsumption set; an implementation MAY emit any subset.</li>
          <li><xref target="iana-extension-fields"/> Initial registry contents are extended with the ten new fields registered in this revision (<tt>result_digest</tt>, <tt>expires_at</tt>, <tt>nonce</tt>, <tt>tool_fingerprint</tt>, <tt>config_manifest_digest</tt>, <tt>cve_inventory_digest</tt>, <tt>executable_hash</tt>, <tt>sbom_digest</tt>, <tt>slsa_provenance_pointer</tt>, <tt>supply_chain_pointer</tt>), each labelled Scope: signed-payload. The four pre-existing entries (<tt>risk_class</tt>, <tt>incident_class</tt>, <tt>counterparty_binding</tt>, <tt>anchors</tt>) are unchanged.</li>
          <li><xref target="iana-type-namespaces"/> Initial registry contents are extended with <tt>protectmcp:observation</tt> (a passive-telemetry receipt emitted under one of the capture topologies of <xref target="capture-topologies"/> when the originating application could not call the SDK directly) and <tt>protectmcp:observation:result_bound</tt> (a follow-up sub-namespace under <tt>protectmcp:observation</tt> for receipts carrying <tt>result_digest</tt> bindings to an originating <tt>protectmcp:decision</tt> receipt via <tt>action_ref</tt>).</li>
          <li>The abstract and <xref target="profile-not-fork"/> overview text are rewritten to enumerate the full extension-field set in five groupings (regulatory classification; cross-agent envelope binding; per-action freshness and integrity plus build-provenance; server-built enforcement attestation; and self-declared threat-framework taxonomy) rather than the legacy "three extension fields" phrasing carried forward from -02 through -04. The wire shape, the signature scope, the canonicalization rule, the hash chain, and the anchoring rules of earlier revisions are unchanged.</li>
          <li>New informative <xref target="related-work"/> cites parallel proposals under the Independent Submissions and individual-draft surfaces of the IETF Datatracker: <xref target="DRAFT-SHARIF-APKI"/> (certificate-based PKI for autonomous AI agents), <xref target="DRAFT-SHARIF-AML"/> (cryptographic attestation across the AI model lifecycle), and <xref target="PIPELOCK-ER2"/> (the Pipelock EvidenceReceipt v2 alternative receipt-format proposal, published as a public reference outside the IETF process). The section is non-exhaustive and is informative; this profile places no normative constraint on a Compliance Receipt implementation by virtue of citing parallel work.</li>
          <li>New informative references: <xref target="DRAFT-SHARIF-APKI"/>, <xref target="DRAFT-SHARIF-AML"/>, <xref target="PIPELOCK-ER2"/>.</li>
          <li>The four-tuple of build-provenance extensions in <xref target="build-provenance"/> is the wire-level surface of the supply-chain notary use case; Deployers under <xref target="EU-AI-ACT"/> Article 12 read together with <xref target="DORA"/> Article 17, under 45 CFR 164.312(b) of <xref target="HIPAA-SECURITY"/>, and under <xref target="SEC-17A-4"/> read with <xref target="NYDFS-500"/> 23 NYCRR 500.6, SHOULD emit at least <tt>executable_hash</tt> on every <tt>protectmcp:decision</tt> receipt. The wording is hortatory; the underlying regime obligations remain the load-bearing requirement.</li>
          <li>No changes to the signing algorithms, the canonicalization transformation (JCS), the hash-chain scope corrected in <xref target="cl-04"/>, the anchor type set, the retention floors of Sections 5 and 6, the Audit Pack manifest fields, or the verifier reporting fields. A -04 receipt that omits all ten new extensions is a conformant -05 receipt. A -05 receipt that carries any of the ten new extensions remains a conformant <xref target="ACTA-RECEIPTS"/> receipt under the upstream extension semantics of Section 4.2 (verifiers that do not implement the extension ignore it).</li>
          <li>Threat-framework taxonomy subsumption. New normative <xref target="threat-framework"/> defines, and <xref target="iana-extension-fields"/> Initial registry contents are further extended with, eight additional signed-payload entries that the reference cloud implementation, both SDK halves, and the published <tt>/.well-known/governance.json</tt> emit and accept: six caller-supplied taxonomy lists (<tt>mitre_techniques</tt>, <tt>mitre_atlas</tt>, <tt>owasp_llm_top10</tt>, <tt>nist_ai_rmf</tt>, <tt>iso_42001</tt>, <tt>eu_ai_act_articles</tt>), one caller-supplied opaque token (<tt>rfc3161_timestamp</tt>, a base64-encoded TimeStampResp per <xref target="RFC3161"/> preserved verbatim on the receipt for offline TSA chain verification independent of any platform-issued anchors), and one platform-set false-attestation guard boolean (<tt>framework_mappings_self_declared</tt>, set to <tt>true</tt> by the issuing platform whenever any of the six taxonomy lists is populated; a producer-supplied <tt>false</tt> alongside a populated taxonomy field MUST be overridden). The taxonomy fields are not platform-verified; the guard exists so verifiers can tell self-declared classifications apart from platform-verified ones. Pre-existing entries are unchanged. The total Initial registry contents now enumerate twenty-two signed-payload-or-envelope-level fields.</li>
          <li>Durable-anchoring quorum. <xref target="anchoring"/> is extended with a normative OPTIONAL envelope-level <tt>witness_policy</tt> member (a sibling of <tt>payload</tt>, <tt>signature</tt>, and <tt>anchors</tt>) that the reference cloud implementation, both SDK halves, and the published <tt>/.well-known/governance.json</tt> emit and accept. <tt>witness_policy</tt> declares an N-of-M quorum over the <tt>anchors</tt> array: <tt>required</tt> (integer in [1, length of <tt>witnesses</tt>]) and <tt>witnesses</tt> (non-empty array, distinct subset of {<tt>rfc3161</tt>, <tt>opentimestamps</tt>}; Rekor and other transparency-log pointers are rejected). The quorum-met state (reported by the reference implementation as <tt>witness_quorum_met</tt>) is reached only when at least <tt>required</tt> distinct witness types each hold a verifiable inclusion proof; a receipt MUST NOT claim durable anchoring otherwise, extending the false-attestation principle to the anchoring quorum. <xref target="iana-extension-fields"/> Initial registry contents are extended with the <tt>witness_policy</tt> entry, labelled Scope: envelope-level, bringing the total to twenty-three signed-payload-or-envelope-level fields. The baseline single-anchor requirement of <xref target="anchoring"/> is unchanged and continues to apply to every Compliance Receipt regardless of whether <tt>witness_policy</tt> is present.</li>
          <li><xref target="related-work"/> is extended with a cite of <xref target="DRAFT-IETF-SCITT"/> (IETF SCITT architecture) and <xref target="RFC6962"/> (Certificate Transparency Merkle inclusion) as the canonical inclusion-proof prior art that <tt>witness_policy</tt> generalizes; SCITT is framed as complementary (a SCITT Transparent Statement can carry a Compliance Receipt as its payload), closing the append-only-log gap deferred under <xref target="compromised-intermediary"/>. New informative references: <xref target="DRAFT-IETF-SCITT"/>, <xref target="RFC6962"/>.</li>
          <li>Enforcement-attestation extensions. New normative <xref target="enforcement-attestation"/> defines two OPTIONAL server-built signed-payload extension fields that the reference cloud implementation and the published <tt>/.well-known/governance.json</tt> emit: <tt>authorized_under_mandate</tt> (an object recording a self-declared authorizing mandate with <tt>mandate_id</tt>, <tt>issuer_id</tt>, a <tt>scope_digest</tt> over the mandate's authorized-action-types scope, and a <tt>verified</tt> boolean whose <tt>true</tt> value asserts self-declared issuer authority, never platform-verified third-party authorization; the binding is evaluated against the issuing platform's clock and scoped to action types, with no value cap and no counterparty restriction) and <tt>controls_evaluated</tt> (a server-built enumeration of which enforcement controls genuinely fired on the sign, drawn from the closed key set <tt>emergency_halt</tt>, <tt>delegation_scope</tt>, <tt>quorum</tt>, <tt>mandate</tt>, <tt>policy</tt>, <tt>content_scan</tt>, <tt>result</tt>, where an absent key means the control did not run rather than that it passed silently). Both fields are server-built, never request inputs; a caller-supplied value is dropped before signing. Each field carries a false-attestation guard that rejects a present-but-malformed attestation at signing time. <xref target="iana-extension-fields"/> Initial registry contents are extended with the two new entries, each labelled Scope: signed-payload, bringing the total to twenty-five signed-payload-or-envelope-level fields.</li>
          <li><xref target="related-work"/> is further extended with a cite of <xref target="A2A"/> (the Agent2Agent protocol, a Linux Foundation project with an Agent Card, an extension mechanism, and an Agent Card JSON Web Signature), <xref target="A2A-IDF"/> (the Agent Identity Verification and Trust Framework proposal under the A2A contribution process, framed as the identity-anchoring layer beneath this profile's per-action receipts), and <xref target="DRAFT-HOPLEY-X402"/> (the closest parallel receipt format: a JCS-canonicalized, SHA-256 hash-chained Compliance Receipt with an ALLOW, REFER, or DENY admission verdict bound to a payment mandate under the x402 substrate). This profile is framed as the broader superset of the x402 format: general agent-action receipts across regulatory regimes rather than payment screening alone, neutral third-party signing rather than self-signing by the screening party, organization-wide control attestation via <tt>controls_evaluated</tt> rather than a single admission verdict, and ML-DSA-65 post-quantum signing. New informative references: <xref target="A2A"/>, <xref target="A2A-IDF"/>, <xref target="DRAFT-HOPLEY-X402"/>.</li>
        </ul>
      </section>
      <section anchor="cl-04" numbered="false"><name>Changes in draft -04</name>
        <t>Cross-agent integrity revision. The threat case is a compromised intermediary that swaps payload bytes between two honest agents while both per-agent hash chains validate independently.</t>
        <ul>
          <li><xref target="hash-chain"/> digest-scope correction. The chain-link digest scope is the canonical signing-input bytes (the JCS-canonical serialization of the predecessor's signed payload object, the same bytes the predecessor's signature covers), NOT the envelope object that additionally includes the <tt>signature</tt> or <tt>anchors</tt> top-level keys. The earlier -04 text that said the digest covers "the entire signed receipt object including the signature field" was a Security Considerations over-reach that did not match the reference implementation and would have required every deployed chain to be re-issued. The corrected scope matches both the reference implementation and the upstream <xref target="ACTA-RECEIPTS"/> Section 5.7 rule. The security rationale is updated accordingly: the chain binds the signed-over content of the predecessor (recomputable offline from the predecessor's payload alone), and cross-agent envelope-including-signature integrity is delegated to <tt>counterparty_binding</tt> (<xref target="counterparty-binding"/>), which IS at the envelope-including-signature scope precisely because the peer signature is the load-bearing artefact in that case. <xref target="mandatory-checks"/> is updated to match.</li>
          <li>New informative <xref target="chain-availability"/> in Security Considerations acknowledges that the single-linear per-agent chain rule of <xref target="hash-chain"/> creates a per-issuer serialization bottleneck: a denial-of-service against the predecessor pointer (database lock, network partition, slow IO) bounds chain throughput. Mitigation: issuers SHOULD use bounded predecessor-lookup timeouts, emit a structured <tt>protectmcp:lifecycle</tt> audit event with a stable <tt>chain_emission_blocked</tt> reason code when the timeout fires, and document a chain-head recovery procedure for crashed emitters. Parallel per-issuer throughput beyond a single linear chain remains the existing distinct-<tt>issuer_id</tt> escape hatch.</li>
          <li><xref target="compromised-intermediary"/> residual list is rewritten for honesty. The M+B collusion residual is downgraded from "M+B alone defeats <tt>counterparty_binding</tt>" to "M+B+(A's-storage compromise or unavailability) defeats <tt>counterparty_binding</tt>": the audit-time verifier resolves <tt>receipt_ref</tt> to A's retained envelope and recomputes the digest, so an honest reachable A's storage defeats M+B collusion alone. A new M+A collusion residual is added: M and A coordinating to produce a fraudulent A-signed envelope is fundamentally outside the receipt model's threat surface because every cryptographic invariant holds; mitigation is separation of duties between issuer and intermediary plus anchor evidence on independent witnesses under different trust roots.</li>
          <li>The worked-example appendix carries an explicit disclaimer that the keys are shown in human-readable order (not JCS-canonical lexicographic order), the <tt>sig</tt>/<tt>value</tt>/<tt>hash</tt> bytes are deterministic placeholders, and implementations MUST NOT replay or trust the example as a real receipt. The disclaimer states the JCS-canonical key ordering that an implementer would derive on the wire.</li>
          <li><xref target="counterparty-binding-wire"/> <tt>envelope_hash</tt> rule is tightened on three axes. First, the base64 alphabet is no longer ambiguous: standard base64 per <xref target="RFC4648"/> Section 4 on emission, OR base64url per Section 5 where the transport requires URL-safe encoding, and verifiers MUST accept both and normalise before comparison. Second, JSON-framed digest scope is now normative and mandatory-to-implement: the JCS-canonical UTF-8 byte sequence of A's signed envelope JSON object per <xref target="RFC8785"/>, where the envelope is the three-key object <tt>{"payload", "signature", "anchors"}</tt> with <tt>anchors</tt> OPTIONAL and B forbidden from re-canonicalizing or stripping any of the three keys before computing the digest. Third, cross-framing equivalence is explicitly addressed: JCS-canonical JSON, COSE deterministic encoding, and JWS Compact Serialization with JCS-canonical payload produce different byte sequences from the same semantic payload-and-signature, so <tt>envelope_hash</tt> is framing-specific; a transcoding intermediary that re-frames A's envelope MUST be treated as a tampering event, and verifiers MUST NOT reframe before recomputing.</li>
          <li><xref target="iana-extension-fields"/> entries now carry an explicit Scope tag (<tt>signed-payload</tt> for <tt>risk_class</tt>, <tt>incident_class</tt>, <tt>counterparty_binding</tt>; <tt>envelope-level</tt> for <tt>anchors</tt>). The CWT claim request for <tt>counterparty_binding</tt> now proposes allocation from the IANA First Come First Served range of <xref target="RFC8392"/> Section 9.1 rather than the unqualified "unassigned integer range" placeholder, so as not to consume Expert Review or Standards Action space.</li>
          <li>The <xref target="CIRCIA"/> reference is corrected to cite the statutory authority (Public Law 117-103 Division Y, codified at 6 U.S.C. 681 et seq.) rather than CISA's general topic page; the March 15, 2022 enactment date is retained, and the pending NPRM at 89 FR 23644 (April 4, 2024) is named in the reference annotation.</li>
          <li>New normative Section 4.6 (<xref target="counterparty-binding"/>) defines the <tt>counterparty_binding</tt> extension field, an in-payload object carrying a base64-encoded SHA-256 digest (<tt>envelope_hash</tt>) over the full signed envelope of a peer agent (including the peer's signature bytes), a resolvable opaque <tt>receipt_ref</tt>, an OPTIONAL <tt>expect_ack_from</tt> identifier (kid/issuer_id of the expected acknowledger), and an OPTIONAL operational <tt>transport_label</tt>. Section 4.6.3 (<xref target="counterparty-binding-verifier"/>) defines the MUST-reject rule when the bound digest does not resolve, the storage obligation on the Audit Pack production layer, and the pairwise default for N-greater-than-2 chains.</li>
          <li>The <tt>anchors</tt> top-level array schema is now defined inline in <xref target="anchoring"/>: each entry MUST carry <tt>type</tt> and <tt>value</tt> (base64-encoded anchor token bytes), with OPTIONAL informational <tt>status</tt> (<tt>anchored</tt> / <tt>pending</tt> / <tt>failed</tt>) and <tt>bitcoin_block</tt> (Bitcoin block hash for upgraded OpenTimestamps entries). The IANA Extension Fields Registry entry for <tt>anchors</tt> is updated to reflect the four-member schema.</li>
          <li>The IANA Type Namespaces Registry initial contents now include the registered sub-namespace <tt>protectmcp:lifecycle:configuration_change</tt> emitted by the reference cloud implementation for configuration-change receipts under <xref target="art12-1"/>.</li>
          <li>CIRCIA retention floor (<xref target="circia-retention"/>) is rewritten to measure two years from the submission of the most recently required CIRCIA report per proposed Section 226.13(c) of the CIRCIA NPRM at 89 FR 23644 (April 4, 2024), not from the date of the underlying Action.</li>
          <li>HIPAA retention (<xref target="hipaa-retention"/>) is rewritten to cite 45 CFR 164.316(b)(2) with the six-year floor expressed as "six years from the date of creation or the date when last in effect, whichever is later" and the analogy basis for applying that floor to audit-log content explicitly named.</li>
          <li>EU AI Act Article 26(6) retention (<xref target="art12-retention"/>) is rewritten to express the six-month floor in calendar-arithmetic terms per <xref target="ISO8601-2"/>; the 184-day day-count figure is retained as an informative anchoring-interval floor, and the previously-endorsed 183-day pick is withdrawn.</li>
          <li><xref target="issuer-id"/> now states explicitly that <tt>issuer_id</tt> values MUST be bare identifiers without a scheme prefix where the scheme is unambiguous (LEI: 20-character alphanumeric self-identifying form), aligning the spec with the reference cloud emitter under the cloud-wire-conformance change.</li>
          <li>New informative Section 9.11 (<xref target="compromised-intermediary"/>) documents the residual threat that <tt>counterparty_binding</tt> partially mitigates (M silently swaps bytes between honest A and B) and names three operational mitigations Operators SHOULD adopt: multiple independent anchor witnesses, regulator-driven side-by-side chain comparison under SEC 17a-4 audit-trail workflow, and out-of-band M relay logs.</li>
          <li>Section 7 (<xref target="audit-pack"/>) records two manifest-level fields shipped in the reference Audit Pack producer: <tt>regime_mapping_disclaimer</tt> (when per-receipt regime predicates derive from a producer-side mapping the original signer did not co-sign) and <tt>stale_pending</tt> (per-entry flag set when anchor evidence remains <tt>pending</tt> after the bound of <xref target="anchoring"/>).</li>
          <li>Section 8.3 (<xref target="reporting"/>) replaces the prior one-paragraph clause with five SHOULD-emit per-axis fields: <tt>regimes_satisfied</tt>, <tt>anchor_valid_ots</tt>, <tt>anchor_valid_rfc3161</tt>, <tt>policy_digest_resolved</tt>, <tt>duplicate_emission_candidate</tt>.</li>
          <li>New informative Section 9.9 (<xref target="issuer-misrep"/>) enumerates the residuals <tt>counterparty_binding</tt> does not solve. New informative Section 9.10 (<xref target="trust-boundary"/>) records channel-level operator guidance citing <xref target="RFC8446"/>, <xref target="RFC9266"/>, <xref target="RFC5705"/>, and <xref target="RFC9421"/> and disclaims transport-layer security as a substitute for application-layer byte equality.</li>
          <li>Section 11 (<xref target="iana"/>) adds <tt>counterparty_binding</tt> to the Extension Fields Registry and requests registration as a CWT claim per <xref target="RFC8392"/>.</li>
          <li>New normative references: <xref target="RFC9052"/>, <xref target="RFC8949"/>, <xref target="RFC7515"/>, <xref target="RFC8392"/>. New informative references for channel-level guidance only: <xref target="RFC8446"/>, <xref target="RFC5705"/>, <xref target="RFC9266"/>, <xref target="RFC9421"/>.</li>
          <li>New normative <xref target="canonicalization-scope"/> bounds the inputs to which the inherited JCS rule of <xref target="RFC8785"/> is applied: IEEE-754 floating-point numbers MUST NOT appear in the digest-covered canonical form (callers SHOULD serialize numerics as JSON strings or as integer-rational pairs in the IEEE-754 safe range), and tool-version-specific semantic equivalence (SQL case folding, path normalization, locale-aware string collation, numeric tolerance, URL percent-encoding choices) is OUT OF SCOPE for the chain layer. The chain answers byte equality for one agent identity at one wall-clock time only; semantic equivalence belongs in the <tt>policy_digest</tt> artefact and the Audit Pack manifest.</li>
          <li><xref target="hash-chain"/> now states explicitly that each issuer MUST maintain a single linear per-agent chain and MUST serialize concurrent in-agent emission (parallel tool calls, thread-pool fan-out) through a single predecessor pointer in emission order. Parallel sub-chains within one agent identity (a per-receipt <tt>chain_id</tt> discriminator) are NOT defined by this profile; an issuer that requires parallel sub-chains MUST express each parallel path as a distinct agent identity with its own <tt>issuer_id</tt>, signing key, and chain rooted at the all-zero genesis value.</li>
          <li>Wire tightenings introduced in this revision (additive at the message level, restrictive at the verifier level): (a) the <tt>anchors</tt> entry <tt>value</tt> member is now REQUIRED where the upstream profile leaves it OPTIONAL; (b) issuer chains are normatively single-linear per issuer (no parallel <tt>chain_id</tt> discriminator), so a -03 producer that ran parallel sub-chains under one <tt>issuer_id</tt> emits non-conformant -04 receipts; and (c) IEEE-754 floating-point numbers MUST NOT appear in the canonical form covered by SHA-256 digests. A -03 receipt with a missing anchor <tt>value</tt>, parallel sub-chains, or a digest-covered float is not a conformant -04 receipt. Implementations targeting -04 SHOULD re-emit -03 receipts under -04 emission rules. The signing algorithms, the canonicalization transformation itself (JCS), the anchor types, and the regime bindings of Sections 5 and 6 are unchanged. A -03 verifier remains conformant for receipts that do not carry <tt>counterparty_binding</tt>; -03 verifiers encountering the field will ignore it per <xref target="ACTA-RECEIPTS"/> Section 4.2 extension semantics.</li>
          <li>Rationale paragraph of <xref target="canonicalization-scope"/> is rewritten to ground the IEEE-754 float ban on documented divergence between mainstream JSON serializers (Python <tt>json.dumps</tt>, Go <tt>encoding/json</tt>, Java Jackson) and the ECMA-262 Number-to-String algorithm referenced by Section 3.2.2.3 of <xref target="RFC8785"/>, rather than on a misstated claim that JCS itself fails to specify float serialization outside the safe integer range. The Unicode-normalization bullet of <xref target="canonicalization-scope"/> is corrected to acknowledge that Section 3.1 of <xref target="RFC8785"/> mandates as-is preservation of Unicode strings (no NFC default).</li>
          <li>Security Considerations <xref target="tamper"/> is corrected to reflect the tiered DORA deadlines: the four-hour initial-notice clock (with 72-hour intermediate-report and one-month final-report bounds) per DORA Article 17 and the RTS in <xref target="REG-2025-301"/>, rather than a flat 72-hour reporting deadline. New informative reference <xref target="REG-2025-301"/> added.</li>
          <li>The Annex II field 3.23 (Type of the incident) citation in <xref target="extension-fields"/> and the <tt>incident_class</tt> initial-registry entry of <xref target="iana-extension-fields"/> no longer reproduces the enumeration verbatim; verifiers MUST resolve the canonical values from <xref target="REG-2025-302"/> directly.</li>
          <li><xref target="decision-fields"/> extends the wire <tt>decision</tt> vocabulary with <tt>observation</tt>, a fourth value reserved to <tt>type</tt> <tt>protectmcp:lifecycle</tt> for receipts emitted when an Action was signed without any policy evaluation. The new value is the regulator-honest alternative to a misleading <tt>allow</tt> on the "no policy matched" path; emitters MUST refuse to issue a <tt>protectmcp:decision</tt> receipt that carries <tt>observation</tt>, and verifiers MUST reject the combination. The vocabulary-namespace registry entry for <tt>protectmcp:decision</tt> in <xref target="iana-type-namespaces"/> is updated to reflect that <tt>observation</tt> is reserved to <tt>protectmcp:lifecycle</tt>.</li>
          <li>New informative appendix (<xref target="capture-topologies"/>) catalogues six capture topologies an operator can use to emit conformant Compliance Receipts in environments where the originating application code cannot be modified to call the receipt-emitting SDK directly: <tt>in_process_sdk</tt>, <tt>network_proxy</tt>, <tt>browser_extension</tt>, <tt>ebpf_observer</tt>, <tt>mcp_proxy</tt>, <tt>passive_telemetry</tt>. The appendix is non-normative; the <tt>capture_topology</tt> attribute it defines is OPTIONAL at the wire layer and, where present, lives in the Audit Pack manifest entry rather than inside the signed <tt>payload</tt> object, so the topology declaration does not alter signed bytes. The six values form a closed initial vocabulary at this revision; <xref target="capture-vocabulary-registry"/> sketches a future "Compliance Receipt Capture Topologies" IANA registry under the "Compliance Receipts" registry group with Specification Required registration policy per <xref target="RFC8126"/> for a follow-on revision, and names reserved-value avoidance guidance for early extenders.</li>
        </ul>
      </section>
      <section anchor="cl-03" numbered="false"><name>Changes in draft -03</name>
        <t>Multi-jurisdiction consolidation. The European Union profile (formerly the only profile in -02) and the United States profile (formerly the separate draft draft-marques-asqav-us-compliance-receipts-00) are merged into a single document with two regional bindings sections: Section 5 (European Union) and Section 6 (United States). Sections 1 through 4 (Introduction, Conventions, Relationship to upstream, Receipt Field Profile) and Sections 7 through 11 (Audit Pack, Verifier, Security, IANA, Acknowledgements) are shared across both regimes. Conventions terms that differ across regimes are now disambiguated with regime suffixes (Deployer (EU AI Act) vs Deployer (Colorado AI Act); High-Risk AI System (EU AI Act) vs High-Risk AI System (Colorado AI Act)). The <tt>incident_class</tt> extension field now lists every applicable canonical category in one place: ICT-related incident under <xref target="DORA"/> with the Annex II reporting enumeration, Cybersecurity Event/Incident under <xref target="NYDFS-500"/>, Covered Cyber Incident under <xref target="CIRCIA"/>, and security incident under <xref target="HIPAA-SECURITY"/>. The <tt>issuer_id</tt> rule now permits EIN or CIK as alternatives to LEI for US Deployers without an allocated LEI. The Tamper Resistance security consideration extends the one-hour anchoring SHOULD to NYDFS 500.17 and CIRCIA in addition to DORA Article 17. The Privacy security consideration extends to GDPR for EU data subjects and CCPA / VCDPA / HIPAA Privacy Rule for US data subjects. The Worked Example notes that the wire shape applies identically to US bindings, with only the <tt>issuer_id</tt> identifier and the vocabularies differing. IANA registries are unchanged; the Initial registry contents for <tt>incident_class</tt> now describe the multi-regime category set. No changes to the wire format, the field profile, the hash chain, the anchoring rules, the Audit Pack contents, or the Verifier checks. Section 4.1.6 (sandbox_state) and Section 4.5 (risk_class) corrected to attribute the EU risk-management documentation requirement to Article 9 of <xref target="EU-AI-ACT"/> (Provider's risk management system) rather than Article 26, with Article 26(1) cited as the deployer's instructions-for-use obligation that links to the Provider's Article 9 documentation. Section 6.5.3 (nydfs-retention) corrected to a single-tier five-year floor under 23 NYCRR 500.6(b) (verified verbatim against LII Cornell); the prior tiered 5-year/3-year split (claimed against the DFS Second Amendment) was incorrect because the Second Amendment does not amend Section 500.6, leaving the 2017 single-tier text in force. The 1096-day three-year audit-trail floor previously stated for NYDFS is removed.</t>
      </section>
      <section anchor="cl-02" numbered="false"><name>Changes in draft -02</name>
        <t>Submission-ready EU-only profile. Wire-shape alignment with upstream <xref target="ACTA-RECEIPTS"/> (<tt>payload</tt>/<tt>signature</tt>/<tt>anchors</tt> envelope; <tt>payload_digest</tt> object form; <tt>tool_name</tt> REQUIRED for <tt>protectmcp:decision</tt>; <tt>issuer_id</tt> equals <tt>kid</tt>). EU AI Act and DORA bindings authored against Official Journal text. Anchor MUST (at least one of RFC 3161 or OpenTimestamps); both RECOMMENDED; 7-day OpenTimestamps upgrade deadline profile-imposed. Six-month AI Act floor expressed as 184 days; DORA-bound default expressed as 1827 days. IANA registries created.</t>
      </section>
      <section anchor="cl-01" numbered="false"><name>Changes in draft -01</name>
        <t>Initial wire-shape alignment with upstream and addition of dual-anchor, hash-chain, retention, and DORA classification bindings. Subsequent revisions superseded the specific values introduced here.</t>
      </section>
      <section anchor="cl-00" numbered="false"><name>Changes in draft -00</name>
        <t>Initial version. Defines a profile of <xref target="ACTA-RECEIPTS"/> that binds receipt fields to EU AI Act Article 12, EU AI Act Article 26, and DORA Article 17.</t>
      </section>
    </section>

    <section anchor="capture-topologies" numbered="false"><name>Appendix - Capture Topologies for Compliance Receipt Emission</name>
      <t>This appendix is informational and non-normative. It catalogues six capture topologies an operator can use to emit conformant Compliance Receipts in environments where the originating application code cannot be modified to call the receipt-emitting SDK directly. The topologies are listed in order of payload fidelity, from highest (in-process SDK, full payload digest) to lowest (passive telemetry, post-hoc log ingestion only). All six emit receipts that satisfy the wire profile of Sections 3 and 4; they differ in trust boundary, payload coverage, and the operational identity that the receipt binds. The intent is to give an operator vocabulary for declaring which topology produced a given receipt, so that a verifier or auditor can interpret the receipt's evidentiary weight without re-deriving the architecture from out-of-band documentation.</t>
      <t>An operator MAY declare the producing topology by including a <tt>capture_topology</tt> attribute in the Audit Pack manifest entry for the receipt. The attribute is informational at the wire layer and OPTIONAL. The vocabulary defined below is closed for the topologies catalogued in this appendix; future revisions or third-party profiles MAY extend it through the future-IANA-registry mechanism noted at the end of this appendix.</t>

      <section anchor="capture-in-process-sdk" numbered="false"><name>In-Process SDK</name>
        <t>The originating application links the receipt-emitting SDK directly and calls it inline with the action being recorded. This is the baseline pattern <xref target="ACTA-RECEIPTS"/> and Sections 3 and 4 of this document are written against. The receipt carries a full <tt>payload_digest</tt> covering the action's request bytes; the SDK has direct access to the application's principal identity, the policy decision, and the request body. Vocabulary value: <tt>in_process_sdk</tt>. Trust boundary: the application process itself; the SDK runs inside the application's memory space and inherits its principal. Threat-model note: captures the full request and response payloads, the deciding principal, and the policy context; does NOT capture out-of-process side effects or actions taken by sibling processes that do not link the SDK. Reference implementation hint: the Asqav Python and TypeScript SDKs published under the asqav-sdk umbrella (Apache-2.0) implement this pattern; an operator MAY substitute any other conformant <xref target="ACTA-RECEIPTS"/> implementation.</t>
      </section>

      <section anchor="capture-network-proxy" numbered="false"><name>Network-Layer Egress Proxy</name>
        <t>A customer-owned reverse proxy or egress gateway (Envoy, NGINX, or an equivalent forward proxy) sits in the network path between the application and the downstream LLM provider. The proxy tees the request to a co-located Compliance Signer process, which receives the request bytes, applies the policy evaluation, and emits a receipt via a signer RPC. A DNS-rewrite on-ramp (CoreDNS rewriting the LLM hostname to the proxy address) or a Server Name Indication (SNI) router (SNIProxy at Layer 4) MAY be used to force application traffic onto the proxy without per-application configuration. Vocabulary value: <tt>network_proxy</tt>. Trust boundary: the customer's network egress; the proxy and signer run under the customer's operational control, and the receipt is signed by a key the customer's signer holds. Threat-model note: captures the request and response bytes that traverse the proxy and the network-layer principal identity (source IP, mTLS client cert if present); does NOT capture traffic that bypasses the proxy (direct outbound from a non-routed host, DNS-over-HTTPS to a hard-coded resolver, or TLS connections to certificate-pinned endpoints that the customer's enterprise CA cannot inspect). The receipt's <tt>issuer_id</tt> binds the customer's signer, not the originating application; the application's identity, where captured, appears as an attribute resolved through the Audit Pack manifest. Reference implementation hint: CoreDNS (Apache-2.0) for the DNS on-ramp, SNIProxy by dlundquist (BSD-2-Clause) for the SNI router, and Envoy (Apache-2.0) for the Layer-7 reverse proxy plane; none of these are normative requirements.</t>
      </section>

      <section anchor="capture-browser-extension" numbered="false"><name>Browser Extension</name>
        <t>A managed-browser Manifest V3 (MV3) extension installed on employee workstations via the enterprise Mobile Device Management (MDM) system intercepts <tt>fetch</tt>, <tt>XMLHttpRequest</tt>, and EventSource requests to a configured list of LLM hostnames. The extension POSTs the intercepted request and response bytes to a Compliance Signer endpoint, which emits the receipt. For LLM hosts that pin their TLS certificates, the customer's enterprise root Certificate Authority (CA) MUST be installed in the browser trust store via MDM so that the extension's content-script interception can observe decrypted bytes. Vocabulary value: <tt>browser_extension</tt>. Trust boundary: the managed browser process on the employee workstation; the extension runs under the browser's sandbox and the employee's interactive session. Threat-model note: captures the full request and response payload for LLM calls initiated from the browser by the human user, and binds the receipt to the browser's principal identity (the user's enterprise single-sign-on subject, where the extension can read it). Does NOT capture LLM calls made by native desktop applications, server-side daemons, or browsers without the extension installed; does NOT capture traffic in incognito or private-window modes unless the extension is explicitly authorised for those contexts. Reference implementation hint: the open-source Chrome MV3 extension scaffolding published by Google under the chrome-extensions-samples repository (Apache-2.0) is a useful starting point; the customer's signer endpoint is the Asqav signer or any conformant <xref target="ACTA-RECEIPTS"/> implementation.</t>
      </section>

      <section anchor="capture-ebpf-observer" numbered="false"><name>eBPF SNI Observer</name>
        <t>A kernel-level extended Berkeley Packet Filter (eBPF) probe attached to the host's network stack observes outbound TLS ClientHello records. The probe extracts the SNI hostname, the JA3 client fingerprint, the source and destination addresses and ports, and the connection timestamp, and emits a lower-fidelity receipt that binds the employee, the device, the wall-clock time, and the LLM host without observing payload content. Vocabulary value: <tt>ebpf_observer</tt>. The receipt SHOULD carry an informational <tt>payload_capture</tt> attribute set to <tt>false</tt> in the Audit Pack manifest, so that a verifier or auditor does not assume payload-level evidence is recoverable. Trust boundary: the kernel of the host on which the probe runs; the probe operates below the application's user-space process and observes traffic regardless of application configuration. Threat-model note: captures the existence and counterparty of an LLM call (the "did the call happen" evidence class) and the device-and-employee binding through host attestation; does NOT capture request or response bytes, the prompt content, the model parameters, or the decision-relevant context. Useful when payload capture is operationally infeasible (TLS certificate pinning that the enterprise CA cannot defeat, third-party SaaS that egresses outside the customer's proxy plane) but the operator still needs evidence that a regulated LLM interaction occurred. Reference implementation hint: Inspektor Gadget (Apache-2.0) and Tetragon (Apache-2.0) both expose SNI and connection-metadata events from eBPF probes; neither is a normative requirement.</t>
      </section>

      <section anchor="capture-mcp-proxy" numbered="false"><name>MCP Transparent Proxy</name>
        <t>A transparent proxy sits in-path between a Model Context Protocol (MCP) client and one or more downstream MCP servers, terminating the client's <tt>stdio</tt>, Server-Sent Events (SSE), or streamable-HTTP transport on one side and re-establishing the same transport to each downstream server on the other side. The proxy observes every <tt>tools/call</tt> and <tt>resources/read</tt> JSON-RPC method invocation, signs a receipt at the moment the call is forwarded, and emits a second acknowledging receipt carrying a <tt>counterparty_binding</tt> (see <xref target="counterparty-binding"/>) at the moment the downstream server's response returns. Both sides of the call are therefore bound bilaterally, with the proxy's signing key serving as the integrity anchor for the pair. Vocabulary value: <tt>mcp_proxy</tt>. The receipt SHOULD carry the invoked MCP method (for example, <tt>tools/call</tt> or <tt>resources/read</tt>) as an attribute in the Audit Pack manifest entry, so that a verifier can filter by call type without re-parsing payload bytes. Trust boundary: the proxy process and its signing key; the upstream MCP client and the downstream MCP server are both treated as honest endpoints under the threat model of <xref target="compromised-intermediary"/>, with the proxy itself being the named intermediary whose tampering risk <tt>counterparty_binding</tt> mitigates. Threat-model note: captures the full MCP request and response payload, the method name, and the client and server principal identities visible at the transport boundary; does NOT capture MCP traffic that bypasses the proxy or that uses a transport the proxy does not implement. Reference implementation hint: the Asqav MCP transparent proxy published under the asqav-mcp repository (Apache-2.0) and the upstream FastMCP project (MIT) on which it builds; neither is a normative requirement.</t>
      </section>

      <section anchor="capture-passive-telemetry" numbered="false"><name>Passive Telemetry Ingestion</name>
        <t>A passive ingestion pipeline reads structured records the originating application or its runtime has already emitted (for example, OpenTelemetry spans, application access logs, vendor-managed observability exports, or batch CSV drops) and synthesises a Compliance Receipt for each record after the fact. The synthesiser holds the signing key, applies the receipt-format wire profile, and emits the receipt to the same downstream sink that the in-process SDK and network-proxy paths feed. Vocabulary value: <tt>passive_telemetry</tt>. The receipt SHOULD carry an informational <tt>payload_capture</tt> attribute set to the value the underlying telemetry source actually preserved (full body, headers only, or none), so that a verifier or auditor can interpret the receipt's evidentiary weight against the upstream pipeline's retention policy. Trust boundary: the telemetry pipeline operator's signing key plus the integrity of the upstream observability source; the receipt binds the producer of the telemetry, not the originating application's per-request principal. Threat-model note: captures whatever the upstream telemetry source preserved (typically a subset of the action's bytes and metadata, often without request or response payload) plus the wall-clock and counterparty identifiers visible in the telemetry record; does NOT capture data the upstream source dropped, sampled out, or never emitted, and inherits any tampering risk the upstream source carries between emission and ingestion. Useful when the in-process SDK, network proxy, browser extension, eBPF observer, and MCP proxy topologies are all operationally infeasible (legacy applications without instrumentation hooks, third-party SaaS with read-only export, fleet migrations where the producer has only logs to work from) but the operator still needs a signed evidence artefact tied to the historical action. Reference implementation hint: any OpenTelemetry collector exporter (Apache-2.0) feeding a conformant receipt-emitting signer; the upstream telemetry source is out of scope of this profile.</t>
      </section>

      <section anchor="capture-vocabulary-registry" numbered="false"><name>capture_topology Vocabulary and Considerations for a Future IANA Registry</name>
        <t>The six values defined in this appendix (<tt>in_process_sdk</tt>, <tt>network_proxy</tt>, <tt>browser_extension</tt>, <tt>ebpf_observer</tt>, <tt>mcp_proxy</tt>, <tt>passive_telemetry</tt>) form the closed initial vocabulary for the <tt>capture_topology</tt> attribute. The attribute is OPTIONAL at the wire layer and, where present, MUST appear in the Audit Pack manifest entry for the receipt rather than inside the signed <tt>payload</tt> object, so that the topology declaration is producer-side metadata that does not alter the receipt's signed bytes. A verifier MUST NOT treat the absence of a <tt>capture_topology</tt> attribute as a non-conformance condition; absence simply means the producer did not declare a topology.</t>
        <t>This document is an Independent Submission and does not request IANA action for the <tt>capture_topology</tt> vocabulary at this revision. A future revision MAY request creation of a "Compliance Receipt Capture Topologies" registry under the same "Compliance Receipts" registry group described in <xref target="iana"/>, with the registration policy of Specification Required per <xref target="RFC8126"/> and an initial set populated from the six values above. Until such a registry exists, implementations that extend the vocabulary SHOULD document the new value in a reference specification and SHOULD avoid colliding with the six reserved values above. The Designated Expert(s) for any future registry SHOULD verify that a candidate value names a distinct topology (a different trust boundary or a materially different payload-fidelity class) rather than a variant of an existing one, and that the candidate's threat-model note states what is captured and what is not, in the form used by the six entries in this appendix.</t>
      </section>
    </section>
  </back>
</rfc>
