diff --git a/src/constants.js b/src/constants.js
new file mode 100644
index 0000000..49a922c
--- /dev/null
+++ b/src/constants.js
@@ -0,0 +1,31 @@
+/**
+ * @veritasacta/verify: Single-source-of-truth constants
+ *
+ * Strings and identifiers that MUST stay byte-identical across the CLI,
+ * the test-vectors generator, and any future conformance-test runner.
+ * Importing from one place prevents docs/code drift from silently
+ * desynchronizing rejection-path semantics.
+ *
+ * Add a new constant here when:
+ *   - a fixture's `expected_result.error` should match the CLI's output
+ *     verbatim, AND
+ *   - the string is normatively pinned to a spec section (cite the
+ *     normative reference in the JSDoc comment).
+ */
+
+/**
+ * Rejection error: APS verification key transported inside the receipt
+ * envelope without an independent anchor (sidecar JWKS, DID resolution,
+ * or other independently anchored key reference).
+ *
+ * Pinned to draft-farley-acta-signed-receipts-02 Security Considerations.
+ *
+ * Used by:
+ *   - test-vectors/generate.mjs → cross-verify-embedded-key-bundle.json
+ *     `expected_result.error` and `expected_verification.error`
+ *   - src/verifier.js (forthcoming v0.7+ enforcement landing) → emitted
+ *     when a bundle declares `external_receipts.aps.signing_key` without
+ *     an accompanying `verification_key_ref`.
+ */
+export const REJECTION_ERROR_EMBEDDED_KEY =
+  'verification key transported inside receipt without independent anchor';
diff --git a/test-vectors/README.md b/test-vectors/README.md
index 1378f2d..2f230cf 100644
--- a/test-vectors/README.md
+++ b/test-vectors/README.md
@@ -11,7 +11,9 @@ Shipped to support the cross-verify work tracked in
 | File | Purpose |
 |------|---------|
 | [`jcs-test-vectors.json`](jcs-test-vectors.json) | JCS canonicalization conformance. 9 cases. Feed each `input` to your canonicalizer and compare the output string and SHA-256 to the expected values. Includes the AIP-0001 ASCII-only key restriction case. |
-| [`cross-verify-bundle.json`](cross-verify-bundle.json) | One complete Knowledge Unit: 4 models × 2 rounds + 1 synthesis + 1 aggregate = 10 Ed25519-signed receipts, hash-chained via `payload.previousReceiptHash`. Includes an `external_receipts.aps` slot for an APS `DecisionLineageReceipt` to drop in. |
+| [`cross-verify-bundle.json`](cross-verify-bundle.json) | MUST accept. One complete Knowledge Unit: 4 models × 2 rounds + 1 synthesis + 1 aggregate = 10 Ed25519-signed receipts, hash-chained via `payload.previousReceiptHash`. Includes an APS `DecisionLineageReceipt` whose verification key is independently anchored via [`keys/aps-ku-cross-verify.jwks`](keys/aps-ku-cross-verify.jwks). |
+| [`cross-verify-embedded-key-bundle.json`](cross-verify-embedded-key-bundle.json) | MUST reject in `@veritasacta/verify` v0.7+ once draft-02 enforcement ships. Deliberately preserves the embedded-key anti-pattern so verifiers can prove they reject verification keys transported inside a receipt or bundle without an independent anchor. **Note for current 0.6.0 consumers:** the verifier does not yet enforce this rejection path; running the suite against 0.6.0 will accept this fixture, which is expected. The fixture's purpose is as a regression target for the v0.7+ enforcement landing, not a test of current behavior. |
+| [`keys/aps-ku-cross-verify.jwks`](keys/aps-ku-cross-verify.jwks) | Sidecar JWKS for the APS cross-verification fixture. Referenced by `external_receipts.aps.verification_key_ref`. |
 | [`selective-disclosure-salted-commit.json`](selective-disclosure-salted-commit.json) | AIP-0002 salted SHA-256 commitment reference. The Grok-4.20 round-1 dissenting response is published with `response.position` and `response.confidence` replaced by commitments. The unsigned `witness` block carries salts + plaintext to unlock them. |
 | [`generate.mjs`](generate.mjs) | The generator. Deterministic: same seed produces byte-identical output. Run `node generate.mjs <outdir>` from a workspace with `@veritasacta/artifacts` installed. |
 
@@ -23,6 +25,15 @@ npx @veritasacta/verify test-vectors/cross-verify-bundle.json --bundle
 # → Bundle: VALID
 #   Total: 10  Passed: 10  Failed: 0
 
+# Positive APS cross-layer fixture with sidecar-anchored key
+npx @veritasacta/verify test-vectors/cross-verify-bundle.json \
+  --bundle --jwks test-vectors/keys/aps-ku-cross-verify.jwks
+
+# Negative embedded-key fixture
+npx @veritasacta/verify test-vectors/cross-verify-embedded-key-bundle.json --bundle
+# → MUST fail non-zero:
+#   verification key transported inside receipt without independent anchor
+
 # Selective-disclosure receipt (redacted shape, signature over redacted payload)
 npx @veritasacta/verify test-vectors/selective-disclosure-salted-commit.json
 # Note: CLI input shape here is the `redacted_receipt` field; pass it directly
@@ -37,7 +48,12 @@ For a third-party canonicalizer + verifier to pass:
 2. For the ASCII-only case, the canonicalizer MUST throw when a key contains non-ASCII.
 3. For `cross-verify-bundle.json`, every receipt individually verifies under the
    `verification.signing_keys[].kid` that matches its `kid` field.
-4. For `selective-disclosure-salted-commit.json`, the redacted receipt verifies
+4. For `cross-verify-bundle.json`, the APS receipt verifier MUST resolve
+   `external_receipts.aps.verification_key_ref` to the sidecar JWKS and MUST NOT
+   rely on a verification key transported inside the receipt or bundle.
+5. For `cross-verify-embedded-key-bundle.json`, a verifier MUST reject with
+   `verification key transported inside receipt without independent anchor`.
+6. For `selective-disclosure-salted-commit.json`, the redacted receipt verifies
    without the witness, and for each entry in `witness.disclosures`:
    `sha256(salt + ":" + JSON.stringify(plaintext))` equals `expected_commitment`.
 
diff --git a/test-vectors/cross-verify-bundle.json b/test-vectors/cross-verify-bundle.json
index cabc406..6a688c7 100644
--- a/test-vectors/cross-verify-bundle.json
+++ b/test-vectors/cross-verify-bundle.json
@@ -60,7 +60,135 @@
         "signature"
       ],
       "receipt_uri": null,
-      "receipt": null
+      "receipt": {
+        "receiptId": "dlr_va_ku_4b3f7c2a9d8e1f05",
+        "timestamp": "2026-04-18T00:00:00Z",
+        "decisionArtifactId": "veritasacta:ku:ku_4b3f7c2a9d8e1f05",
+        "decisionType": "knowledge_unit_deliberation",
+        "contributingSources": [
+          {
+            "sourceId": "ku:model:claude-opus-4.6",
+            "accessReceiptId": "sha256:2b06eb3385bcfa7bf29d59ae693c28124062fdb9b548a9710c1ee44f2eeae192",
+            "derivationDepth": 1,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:model:gpt-5",
+            "accessReceiptId": "sha256:a54dde3a9dd2501476b0e9613990333371a29b2b669c9da02e348a86e6b2ff83",
+            "derivationDepth": 2,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:model:gemini-2.5-pro",
+            "accessReceiptId": "sha256:76cce8f734ae646b56f4df333a15a400f254dcacece06e7b2bf26c97438b8bbc",
+            "derivationDepth": 3,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:model:grok-4.20",
+            "accessReceiptId": "sha256:653a70f396a16d2114b42996305f514b35d5ba59e6b37527b6311aa4d9e79aeb",
+            "derivationDepth": 4,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:model:claude-opus-4.6",
+            "accessReceiptId": "sha256:69eaa88bb7b4d0c66e9649096dae4aad20b84f7d9862b404f46a37e0a96e8240",
+            "derivationDepth": 5,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:model:gpt-5",
+            "accessReceiptId": "sha256:18ac3cef4d85205ebe2886b8b94b368ae8d28585088762e91df80ab3031a42d6",
+            "derivationDepth": 6,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:model:gemini-2.5-pro",
+            "accessReceiptId": "sha256:b69cef75b1f0eeb36ece82755df449ccea4dde04915268c254fef33508ce016f",
+            "derivationDepth": 7,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:model:grok-4.20",
+            "accessReceiptId": "sha256:b744f32a94d8f1f7727e9020308a8b1db87aef8c80b53c7644398ae0078317bc",
+            "derivationDepth": 8,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:arbiter:scopeblind-reference",
+            "accessReceiptId": "sha256:b0b54512737617227b1ac7569c06e71fbe8dd944011050c3ceaeac5e79526122",
+            "derivationDepth": 9,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:arbiter:scopeblind-reference",
+            "accessReceiptId": "sha256:a630e18f8a394f5b8f3488b6d6ffa1ce2193380b3ae35de8b7477b640fdacb6b",
+            "derivationDepth": 10,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          }
+        ],
+        "lineageCompleteness": "complete",
+        "externalHopsPresent": true,
+        "transformChain": [
+          "aggregation"
+        ],
+        "governingPurpose": "research:academic",
+        "jurisdictionContext": "veritasacta:knowledge-unit-bundle:v1",
+        "explanation": "APS DecisionLineageReceipt attesting to VeritasActa Knowledge Unit ku_4b3f7c2a9d8e1f05. Bundle terminal aggregate sha256: a630e18f8a394f5b8f3488b6d6ffa1ce2193380b3ae35de8b7477b640fdacb6b. Each entry in contributingSources commits to the JCS-canonical sha256 of one KU receipt; tampering any byte of any KU receipt invalidates the recorded accessReceiptId, breaking cross-layer integrity even though APS's Ed25519 signature over this DecisionLineageReceipt remains cryptographically valid.",
+        "signature": "c4ff9a5142ddf133294ccbbbed55facf077df11e3b067627fd041277832a0e5865d74d32845aac6486242aca2b8d52142699bc6c3fe8b4f0bf987e2b56001001"
+      },
+      "verifier_hint": "Verify APS DecisionLineageReceipt using the independently anchored key referenced by external_receipts.aps.verification_key_ref. Cross-layer integrity: each contributingSources[].accessReceiptId is the JCS-canonical sha256 of the corresponding entry in bundle.receipts.",
+      "verification_key_ref": "test-vectors/keys/aps-ku-cross-verify.jwks#aps-ku-cross-verify-v1"
     }
   },
   "receipts": [
diff --git a/test-vectors/cross-verify-embedded-key-bundle.json b/test-vectors/cross-verify-embedded-key-bundle.json
new file mode 100644
index 0000000..e7645d4
--- /dev/null
+++ b/test-vectors/cross-verify-embedded-key-bundle.json
@@ -0,0 +1,483 @@
+{
+  "format": "veritasacta:knowledge-unit-bundle:v1",
+  "spec": "draft-farley-acta-knowledge-units-00",
+  "ku_id": "ku_4b3f7c2a9d8e1f05",
+  "generated_at": "2026-04-17T12:00:00Z",
+  "description": "Complete Knowledge Unit deliberation: 4 models × 2 rounds + 1 synthesis + 1 aggregate = 10 Ed25519-signed receipts. Hash-chained via payload.previousReceiptHash over JCS-canonical bytes. Every receipt is individually verifiable with @veritasacta/verify; the bundle is verifiable with --bundle.",
+  "verification": {
+    "signing_keys": [
+      {
+        "kty": "OKP",
+        "crv": "Ed25519",
+        "kid": "Z-LI5A7pV_q5L0741YBXwcOCo1U13ONImZ4OkQnKkg0",
+        "x": "tiTKo_UAbc-jbX6rtdupskLamLZPIXSC30y6dPPHRWQ",
+        "use": "sig",
+        "issuer": "ku:model:claude-opus-4.6"
+      },
+      {
+        "kty": "OKP",
+        "crv": "Ed25519",
+        "kid": "yH110mxzFmSFg-rqk93G6orppuIMvxJaBBCbtB2BF1Y",
+        "x": "wLeHCJz2lKADNwV1pNMEtFbsbostfaXVjtfhEcauPs4",
+        "use": "sig",
+        "issuer": "ku:model:gpt-5"
+      },
+      {
+        "kty": "OKP",
+        "crv": "Ed25519",
+        "kid": "EOahLGtg57mQJhgTwQc-cTmZZPTVn_NGal6SH5taqJw",
+        "x": "zwJOHnOSOTkkh37-GuNxC41o54UX-Yjnn6FN_1JKJDo",
+        "use": "sig",
+        "issuer": "ku:model:gemini-2.5-pro"
+      },
+      {
+        "kty": "OKP",
+        "crv": "Ed25519",
+        "kid": "MdZxWfPWCPrjb4blQEWBKFyk9FkazXCgk2K7QFiuYRw",
+        "x": "nQIE0pSO6yXnABIt3SdC01oyyLa-J1i9Wf5o1lDUtoc",
+        "use": "sig",
+        "issuer": "ku:model:grok-4.20"
+      },
+      {
+        "kty": "OKP",
+        "crv": "Ed25519",
+        "kid": "YJMzwAk4gkCxTzWPmVAlcLtr517adDfl9gxGCLP4bDw",
+        "x": "Uy9EM6Buox0IJ9Ry0QiPtPuxj-7oZedl3_ogRzpXSd4",
+        "use": "sig",
+        "issuer": "ku:arbiter:scopeblind-reference"
+      }
+    ]
+  },
+  "external_receipts": {
+    "aps": {
+      "description": "Drop-in slot for an APS DecisionLineageReceipt that references ku_id=ku_4b3f7c2a9d8e1f05. When populated, both @veritasacta/verify and agent-passport-system verifiers should exit 0 over the same bundle.",
+      "ku_id": "ku_4b3f7c2a9d8e1f05",
+      "expected_fields": [
+        "subject",
+        "scope",
+        "ku_id",
+        "receipt_hash",
+        "signature"
+      ],
+      "receipt_uri": null,
+      "receipt": {
+        "receiptId": "dlr_va_ku_4b3f7c2a9d8e1f05",
+        "timestamp": "2026-04-18T00:00:00Z",
+        "decisionArtifactId": "veritasacta:ku:ku_4b3f7c2a9d8e1f05",
+        "decisionType": "knowledge_unit_deliberation",
+        "contributingSources": [
+          {
+            "sourceId": "ku:model:claude-opus-4.6",
+            "accessReceiptId": "sha256:2b06eb3385bcfa7bf29d59ae693c28124062fdb9b548a9710c1ee44f2eeae192",
+            "derivationDepth": 1,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:model:gpt-5",
+            "accessReceiptId": "sha256:a54dde3a9dd2501476b0e9613990333371a29b2b669c9da02e348a86e6b2ff83",
+            "derivationDepth": 2,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:model:gemini-2.5-pro",
+            "accessReceiptId": "sha256:76cce8f734ae646b56f4df333a15a400f254dcacece06e7b2bf26c97438b8bbc",
+            "derivationDepth": 3,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:model:grok-4.20",
+            "accessReceiptId": "sha256:653a70f396a16d2114b42996305f514b35d5ba59e6b37527b6311aa4d9e79aeb",
+            "derivationDepth": 4,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:model:claude-opus-4.6",
+            "accessReceiptId": "sha256:69eaa88bb7b4d0c66e9649096dae4aad20b84f7d9862b404f46a37e0a96e8240",
+            "derivationDepth": 5,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:model:gpt-5",
+            "accessReceiptId": "sha256:18ac3cef4d85205ebe2886b8b94b368ae8d28585088762e91df80ab3031a42d6",
+            "derivationDepth": 6,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:model:gemini-2.5-pro",
+            "accessReceiptId": "sha256:b69cef75b1f0eeb36ece82755df449ccea4dde04915268c254fef33508ce016f",
+            "derivationDepth": 7,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:model:grok-4.20",
+            "accessReceiptId": "sha256:b744f32a94d8f1f7727e9020308a8b1db87aef8c80b53c7644398ae0078317bc",
+            "derivationDepth": 8,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:arbiter:scopeblind-reference",
+            "accessReceiptId": "sha256:b0b54512737617227b1ac7569c06e71fbe8dd944011050c3ceaeac5e79526122",
+            "derivationDepth": 9,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          },
+          {
+            "sourceId": "ku:arbiter:scopeblind-reference",
+            "accessReceiptId": "sha256:a630e18f8a394f5b8f3488b6d6ffa1ce2193380b3ae35de8b7477b640fdacb6b",
+            "derivationDepth": 10,
+            "transformPath": [
+              "aggregation"
+            ],
+            "termsVersionAtAccess": "veritasacta:knowledge-unit-bundle:v1",
+            "lineageConfidence": "complete",
+            "compensationStatus": "settled"
+          }
+        ],
+        "lineageCompleteness": "complete",
+        "externalHopsPresent": true,
+        "transformChain": [
+          "aggregation"
+        ],
+        "governingPurpose": "research:academic",
+        "jurisdictionContext": "veritasacta:knowledge-unit-bundle:v1",
+        "explanation": "APS DecisionLineageReceipt attesting to VeritasActa Knowledge Unit ku_4b3f7c2a9d8e1f05. Bundle terminal aggregate sha256: a630e18f8a394f5b8f3488b6d6ffa1ce2193380b3ae35de8b7477b640fdacb6b. Each entry in contributingSources commits to the JCS-canonical sha256 of one KU receipt; tampering any byte of any KU receipt invalidates the recorded accessReceiptId, breaking cross-layer integrity even though APS's Ed25519 signature over this DecisionLineageReceipt remains cryptographically valid.",
+        "signature": "c4ff9a5142ddf133294ccbbbed55facf077df11e3b067627fd041277832a0e5865d74d32845aac6486242aca2b8d52142699bc6c3fe8b4f0bf987e2b56001001"
+      },
+      "signing_key": {
+        "kty": "OKP",
+        "crv": "Ed25519",
+        "use": "sig",
+        "issuer": "aps:test:ku-cross-verify",
+        "public_key_hex": "e91c6bc5b1ae0050db2a84ed962559e977cc6ff4cb5bd11577071bd7fa604faa",
+        "seed_note": "derived from sha256(\"aps:veritasacta:ku-cross-verify:v1\") — test key, NOT a production issuer"
+      },
+      "verifier_hint": "Negative conformance fixture. A verifier MUST reject this bundle because the APS verification key is transported inside external_receipts.aps.signing_key without an independent anchor.",
+      "expected_result": {
+        "verifier": "@veritasacta/verify",
+        "result": "MUST_REJECT",
+        "error": "verification key transported inside receipt without independent anchor"
+      }
+    }
+  },
+  "receipts": [
+    {
+      "v": 2,
+      "type": "veritasacta:knowledge_unit:round_response",
+      "algorithm": "ed25519",
+      "kid": "Z-LI5A7pV_q5L0741YBXwcOCo1U13ONImZ4OkQnKkg0",
+      "issuer": "ku:model:claude-opus-4.6",
+      "issued_at": "2026-04-17T12:00:01Z",
+      "payload": {
+        "ku_id": "ku_4b3f7c2a9d8e1f05",
+        "sequence": 1,
+        "round": 1,
+        "model": {
+          "id": "claude-opus-4.6",
+          "vendor": "anthropic"
+        },
+        "topic_digest": "a0431c892bf3d1d67c63726c9a7cf00c6270b39098c8e9cdcfdf26bb73825b24",
+        "response": {
+          "position": "quadratic",
+          "confidence": 0.72
+        }
+      },
+      "signature": "b51bdf0dd826b63dd84d0e0d50e3700b48a5213adeebaefff7db9c3b109ba935dc70e78189fc0d306b10aa6337e32a8e74e92300e6e7eae91f76a282c2a8b609"
+    },
+    {
+      "v": 2,
+      "type": "veritasacta:knowledge_unit:round_response",
+      "algorithm": "ed25519",
+      "kid": "yH110mxzFmSFg-rqk93G6orppuIMvxJaBBCbtB2BF1Y",
+      "issuer": "ku:model:gpt-5",
+      "issued_at": "2026-04-17T12:00:02Z",
+      "payload": {
+        "ku_id": "ku_4b3f7c2a9d8e1f05",
+        "sequence": 2,
+        "round": 1,
+        "model": {
+          "id": "gpt-5",
+          "vendor": "openai"
+        },
+        "topic_digest": "a0431c892bf3d1d67c63726c9a7cf00c6270b39098c8e9cdcfdf26bb73825b24",
+        "response": {
+          "position": "quadratic",
+          "confidence": 0.65
+        },
+        "previousReceiptHash": "sha256:2b06eb3385bcfa7bf29d59ae693c28124062fdb9b548a9710c1ee44f2eeae192"
+      },
+      "signature": "14fa53712789d72d727ea7c99cf109181b42de2b6baaa76c97f8c0ac1633e667d2888672a181ddf896636e3cabb441ec68d3f4bc23f85a9f47ccc3980619680f"
+    },
+    {
+      "v": 2,
+      "type": "veritasacta:knowledge_unit:round_response",
+      "algorithm": "ed25519",
+      "kid": "EOahLGtg57mQJhgTwQc-cTmZZPTVn_NGal6SH5taqJw",
+      "issuer": "ku:model:gemini-2.5-pro",
+      "issued_at": "2026-04-17T12:00:03Z",
+      "payload": {
+        "ku_id": "ku_4b3f7c2a9d8e1f05",
+        "sequence": 3,
+        "round": 1,
+        "model": {
+          "id": "gemini-2.5-pro",
+          "vendor": "google"
+        },
+        "topic_digest": "a0431c892bf3d1d67c63726c9a7cf00c6270b39098c8e9cdcfdf26bb73825b24",
+        "response": {
+          "position": "depends_on_sequence_length",
+          "confidence": 0.8
+        },
+        "previousReceiptHash": "sha256:a54dde3a9dd2501476b0e9613990333371a29b2b669c9da02e348a86e6b2ff83"
+      },
+      "signature": "fc702aab98cdf8f35c88b90da54776c037bcd53cee00183f4b994367c642558be7c6b1113ca370e24719f0f883a5772e358fb21ec58fa1b7d726e1c03d12930c"
+    },
+    {
+      "v": 2,
+      "type": "veritasacta:knowledge_unit:round_response",
+      "algorithm": "ed25519",
+      "kid": "MdZxWfPWCPrjb4blQEWBKFyk9FkazXCgk2K7QFiuYRw",
+      "issuer": "ku:model:grok-4.20",
+      "issued_at": "2026-04-17T12:00:04Z",
+      "payload": {
+        "ku_id": "ku_4b3f7c2a9d8e1f05",
+        "sequence": 4,
+        "round": 1,
+        "model": {
+          "id": "grok-4.20",
+          "vendor": "xai"
+        },
+        "topic_digest": "a0431c892bf3d1d67c63726c9a7cf00c6270b39098c8e9cdcfdf26bb73825b24",
+        "response": {
+          "position": "linear",
+          "confidence": 0.58
+        },
+        "previousReceiptHash": "sha256:76cce8f734ae646b56f4df333a15a400f254dcacece06e7b2bf26c97438b8bbc"
+      },
+      "signature": "143109c124d8e8c857e1d0e5bc4da432be49a46fec0f77d34ee046e487efd4c2cca6e93697c56b8cec499a23e150dc7a4ea432328c7822092d15055ecf668e06"
+    },
+    {
+      "v": 2,
+      "type": "veritasacta:knowledge_unit:round_response",
+      "algorithm": "ed25519",
+      "kid": "Z-LI5A7pV_q5L0741YBXwcOCo1U13ONImZ4OkQnKkg0",
+      "issuer": "ku:model:claude-opus-4.6",
+      "issued_at": "2026-04-17T12:00:05Z",
+      "payload": {
+        "ku_id": "ku_4b3f7c2a9d8e1f05",
+        "sequence": 5,
+        "round": 2,
+        "model": {
+          "id": "claude-opus-4.6",
+          "vendor": "anthropic"
+        },
+        "topic_digest": "a0431c892bf3d1d67c63726c9a7cf00c6270b39098c8e9cdcfdf26bb73825b24",
+        "response": {
+          "position": "quadratic",
+          "confidence": 0.74,
+          "dissent_from": [
+            "grok-4.20"
+          ]
+        },
+        "previousReceiptHash": "sha256:653a70f396a16d2114b42996305f514b35d5ba59e6b37527b6311aa4d9e79aeb"
+      },
+      "signature": "cdccd1f18914a542625b2f9916729b7584e590c3f224cb8901de3547565f94696893da3db5ce10057334206b8865aef917dbe4e050633761d0c99cc5526dde03"
+    },
+    {
+      "v": 2,
+      "type": "veritasacta:knowledge_unit:round_response",
+      "algorithm": "ed25519",
+      "kid": "yH110mxzFmSFg-rqk93G6orppuIMvxJaBBCbtB2BF1Y",
+      "issuer": "ku:model:gpt-5",
+      "issued_at": "2026-04-17T12:00:06Z",
+      "payload": {
+        "ku_id": "ku_4b3f7c2a9d8e1f05",
+        "sequence": 6,
+        "round": 2,
+        "model": {
+          "id": "gpt-5",
+          "vendor": "openai"
+        },
+        "topic_digest": "a0431c892bf3d1d67c63726c9a7cf00c6270b39098c8e9cdcfdf26bb73825b24",
+        "response": {
+          "position": "depends_on_sequence_length",
+          "confidence": 0.7,
+          "updated_from_round1": true
+        },
+        "previousReceiptHash": "sha256:69eaa88bb7b4d0c66e9649096dae4aad20b84f7d9862b404f46a37e0a96e8240"
+      },
+      "signature": "5db1986b447ae954ee425449c238550244821fb7fd9b928c477375b23b38126cc9aa4f394b727e97ada3ed1646dc1ca0b7dc6ee2f5f390d5c7e8a4dc95ae9c04"
+    },
+    {
+      "v": 2,
+      "type": "veritasacta:knowledge_unit:round_response",
+      "algorithm": "ed25519",
+      "kid": "EOahLGtg57mQJhgTwQc-cTmZZPTVn_NGal6SH5taqJw",
+      "issuer": "ku:model:gemini-2.5-pro",
+      "issued_at": "2026-04-17T12:00:07Z",
+      "payload": {
+        "ku_id": "ku_4b3f7c2a9d8e1f05",
+        "sequence": 7,
+        "round": 2,
+        "model": {
+          "id": "gemini-2.5-pro",
+          "vendor": "google"
+        },
+        "topic_digest": "a0431c892bf3d1d67c63726c9a7cf00c6270b39098c8e9cdcfdf26bb73825b24",
+        "response": {
+          "position": "depends_on_sequence_length",
+          "confidence": 0.85
+        },
+        "previousReceiptHash": "sha256:18ac3cef4d85205ebe2886b8b94b368ae8d28585088762e91df80ab3031a42d6"
+      },
+      "signature": "f6483e7dc42969ac5536f6b65a9ff43305ba2f7404215368e13203f7d5500fb4e2b7537d56a63f1af3f459d0d50b124a43736e7013566548f70958ce4481540b"
+    },
+    {
+      "v": 2,
+      "type": "veritasacta:knowledge_unit:round_response",
+      "algorithm": "ed25519",
+      "kid": "MdZxWfPWCPrjb4blQEWBKFyk9FkazXCgk2K7QFiuYRw",
+      "issuer": "ku:model:grok-4.20",
+      "issued_at": "2026-04-17T12:00:08Z",
+      "payload": {
+        "ku_id": "ku_4b3f7c2a9d8e1f05",
+        "sequence": 8,
+        "round": 2,
+        "model": {
+          "id": "grok-4.20",
+          "vendor": "xai"
+        },
+        "topic_digest": "a0431c892bf3d1d67c63726c9a7cf00c6270b39098c8e9cdcfdf26bb73825b24",
+        "response": {
+          "position": "linear",
+          "confidence": 0.55,
+          "dissent_from": [
+            "claude-opus-4.6",
+            "gpt-5",
+            "gemini-2.5-pro"
+          ]
+        },
+        "previousReceiptHash": "sha256:b69cef75b1f0eeb36ece82755df449ccea4dde04915268c254fef33508ce016f"
+      },
+      "signature": "1801e655c32aff17298399d36471c4049ea75631047858160c9f698cb2dc83981d94bdeda7f5d74d0fb54664cafce206ca25c2d73d51b6a25cb28610de4b840d"
+    },
+    {
+      "v": 2,
+      "type": "veritasacta:knowledge_unit:synthesis",
+      "algorithm": "ed25519",
+      "kid": "YJMzwAk4gkCxTzWPmVAlcLtr517adDfl9gxGCLP4bDw",
+      "issuer": "ku:arbiter:scopeblind-reference",
+      "issued_at": "2026-04-17T12:00:09Z",
+      "payload": {
+        "ku_id": "ku_4b3f7c2a9d8e1f05",
+        "sequence": 9,
+        "round": 3,
+        "synthesis": {
+          "consensus": "depends_on_sequence_length",
+          "consensus_models": [
+            "gpt-5",
+            "gemini-2.5-pro"
+          ],
+          "dissenting_positions": [
+            {
+              "position": "quadratic",
+              "models": [
+                "claude-opus-4.6"
+              ],
+              "mean_confidence": 0.74
+            },
+            {
+              "position": "linear",
+              "models": [
+                "grok-4.20"
+              ],
+              "mean_confidence": 0.55
+            }
+          ],
+          "synthesis_confidence": 0.68
+        },
+        "topic_digest": "a0431c892bf3d1d67c63726c9a7cf00c6270b39098c8e9cdcfdf26bb73825b24",
+        "previousReceiptHash": "sha256:b744f32a94d8f1f7727e9020308a8b1db87aef8c80b53c7644398ae0078317bc"
+      },
+      "signature": "f6023315011bc437c0a1a6222c008affb7e14d264c4c89ad26efd12031461888858bb429eb54b2e26bbe093db53df83e80562d0199f8bdf4ed057178f947840d"
+    },
+    {
+      "v": 2,
+      "type": "veritasacta:knowledge_unit:aggregate",
+      "algorithm": "ed25519",
+      "kid": "YJMzwAk4gkCxTzWPmVAlcLtr517adDfl9gxGCLP4bDw",
+      "issuer": "ku:arbiter:scopeblind-reference",
+      "issued_at": "2026-04-17T12:00:10Z",
+      "payload": {
+        "ku_id": "ku_4b3f7c2a9d8e1f05",
+        "sequence": 10,
+        "aggregate": {
+          "binds_receipts": [
+            "sha256:2b06eb3385bcfa7bf29d59ae693c28124062fdb9b548a9710c1ee44f2eeae192",
+            "sha256:a54dde3a9dd2501476b0e9613990333371a29b2b669c9da02e348a86e6b2ff83",
+            "sha256:76cce8f734ae646b56f4df333a15a400f254dcacece06e7b2bf26c97438b8bbc",
+            "sha256:653a70f396a16d2114b42996305f514b35d5ba59e6b37527b6311aa4d9e79aeb",
+            "sha256:69eaa88bb7b4d0c66e9649096dae4aad20b84f7d9862b404f46a37e0a96e8240",
+            "sha256:18ac3cef4d85205ebe2886b8b94b368ae8d28585088762e91df80ab3031a42d6",
+            "sha256:b69cef75b1f0eeb36ece82755df449ccea4dde04915268c254fef33508ce016f",
+            "sha256:b744f32a94d8f1f7727e9020308a8b1db87aef8c80b53c7644398ae0078317bc",
+            "sha256:b0b54512737617227b1ac7569c06e71fbe8dd944011050c3ceaeac5e79526122"
+          ],
+          "round_count": 3,
+          "model_count": 4,
+          "deliberation_outcome": "synthesis_with_recorded_dissent"
+        },
+        "previousReceiptHash": "sha256:b0b54512737617227b1ac7569c06e71fbe8dd944011050c3ceaeac5e79526122"
+      },
+      "signature": "f160552fbdf28e326eacd639649fc8fe18af6dbe9a2d7a415fa424f4a638dedf77d7fa591a350fcf11ede65fbef07e3d7ea484b2ee2c7de47459097f75a03704"
+    }
+  ],
+  "expected_verification": {
+    "result": "MUST_REJECT",
+    "error": "verification key transported inside receipt without independent anchor",
+    "normative_reference": "draft-farley-acta-signed-receipts-02 Security Considerations"
+  }
+}
diff --git a/test-vectors/generate.mjs b/test-vectors/generate.mjs
index afdeaa2..5beb41e 100644
--- a/test-vectors/generate.mjs
+++ b/test-vectors/generate.mjs
@@ -23,8 +23,10 @@ import {
   hexToBytes,
   sha256,
 } from '@veritasacta/artifacts';
-import { writeFileSync } from 'node:fs';
+import { ed25519 } from '@noble/curves/ed25519';
+import { existsSync, mkdirSync, writeFileSync } from 'node:fs';
 import { createHash } from 'node:crypto';
+import { REJECTION_ERROR_EMBEDDED_KEY } from '../src/constants.js';
 
 // ─── Deterministic seed ──────────────────────────────────────────
 const SEED = 'veritasacta:verify:test-vectors:2026-04-17';
@@ -336,6 +338,87 @@ function buildBundle() {
   };
 }
 
+function buildApsCrossVerifyArtifacts(bundle) {
+  const seed = sha256(new TextEncoder().encode('aps:veritasacta:ku-cross-verify:v1'));
+  const priv = bytesToHex(seed);
+  const pub = ed25519.getPublicKey(seed);
+  const publicKeyHex = bytesToHex(pub);
+  const kid = 'aps-ku-cross-verify-v1';
+  const seedNote = 'derived from sha256("aps:veritasacta:ku-cross-verify:v1") — test key, NOT a production issuer';
+  const issuer = 'aps:test:ku-cross-verify';
+
+  const receipt = {
+    receiptId: `dlr_va_${KU_ID}`,
+    timestamp: '2026-04-18T00:00:00Z',
+    decisionArtifactId: `veritasacta:ku:${KU_ID}`,
+    decisionType: 'knowledge_unit_deliberation',
+    contributingSources: bundle.receipts.map((r, i) => ({
+      sourceId: r.issuer,
+      accessReceiptId: `sha256:${canonicalHash(r)}`,
+      derivationDepth: i + 1,
+      transformPath: ['aggregation'],
+      termsVersionAtAccess: 'veritasacta:knowledge-unit-bundle:v1',
+      lineageConfidence: 'complete',
+      compensationStatus: 'settled',
+    })),
+    lineageCompleteness: 'complete',
+    externalHopsPresent: true,
+    transformChain: ['aggregation'],
+    governingPurpose: 'research:academic',
+    jurisdictionContext: 'veritasacta:knowledge-unit-bundle:v1',
+    explanation:
+      `APS DecisionLineageReceipt attesting to VeritasActa Knowledge Unit ${KU_ID}. Bundle terminal aggregate sha256: ${canonicalHash(bundle.receipts.at(-1))}. Each entry in contributingSources commits to the JCS-canonical sha256 of one KU receipt; tampering any byte of any KU receipt invalidates the recorded accessReceiptId, breaking cross-layer integrity even though APS's Ed25519 signature over this DecisionLineageReceipt remains cryptographically valid.`,
+  };
+  receipt.signature = bytesToHex(ed25519.sign(new TextEncoder().encode(canonicalize(receipt)), hexToBytes(priv)));
+
+  const signingKey = {
+    kty: 'OKP',
+    crv: 'Ed25519',
+    use: 'sig',
+    issuer,
+    public_key_hex: publicKeyHex,
+    seed_note: seedNote,
+  };
+
+  const jwks = {
+    keys: [
+      {
+        kty: 'OKP',
+        crv: 'Ed25519',
+        use: 'sig',
+        kid,
+        x: Buffer.from(pub).toString('base64url'),
+        issuer,
+        seed_note: seedNote,
+      },
+    ],
+  };
+
+  const positive = JSON.parse(JSON.stringify(bundle));
+  positive.external_receipts.aps.receipt = receipt;
+  positive.external_receipts.aps.verification_key_ref = `test-vectors/keys/aps-ku-cross-verify.jwks#${kid}`;
+  positive.external_receipts.aps.verifier_hint =
+    'Verify APS DecisionLineageReceipt using the independently anchored key referenced by external_receipts.aps.verification_key_ref. Cross-layer integrity: each contributingSources[].accessReceiptId is the JCS-canonical sha256 of the corresponding entry in bundle.receipts.';
+
+  const negative = JSON.parse(JSON.stringify(bundle));
+  negative.external_receipts.aps.receipt = receipt;
+  negative.external_receipts.aps.signing_key = signingKey;
+  negative.external_receipts.aps.verifier_hint =
+    'Negative conformance fixture. A verifier MUST reject this bundle because the APS verification key is transported inside external_receipts.aps.signing_key without an independent anchor.';
+  negative.external_receipts.aps.expected_result = {
+    verifier: '@veritasacta/verify',
+    result: 'MUST_REJECT',
+    error: REJECTION_ERROR_EMBEDDED_KEY,
+  };
+  negative.expected_verification = {
+    result: 'MUST_REJECT',
+    error: REJECTION_ERROR_EMBEDDED_KEY,
+    normative_reference: 'draft-farley-acta-signed-receipts-02 Security Considerations',
+  };
+
+  return { positive, negative, jwks };
+}
+
 // ═══════════════════════════════════════════════════════════════════
 // 3. selective-disclosure-salted-commit.json
 // ═══════════════════════════════════════════════════════════════════
@@ -440,11 +523,30 @@ function buildSelectiveDisclosure() {
 
 const jcsVecs = buildJcsVectors();
 const bundle = buildBundle();
+const aps = buildApsCrossVerifyArtifacts(bundle);
 const sdc = buildSelectiveDisclosure();
 
 const outDir = process.argv[2] || '.';
+const forceNegative = process.argv.includes('--force-negative');
+mkdirSync(`${outDir}/keys`, { recursive: true });
 writeFileSync(`${outDir}/jcs-test-vectors.json`, JSON.stringify(jcsVecs, null, 2) + '\n');
-writeFileSync(`${outDir}/cross-verify-bundle.json`, JSON.stringify(bundle, null, 2) + '\n');
+writeFileSync(`${outDir}/cross-verify-bundle.json`, JSON.stringify(aps.positive, null, 2) + '\n');
+
+// Static-fixture preservation: cross-verify-embedded-key-bundle.json is the
+// MUST-reject regression target for the v0.7+ enforcement landing. The
+// generator does not own this fixture's evolution; if a generator change
+// silently rewrites it, the fixture's value as a regression target collapses.
+// Default behavior: skip if the file already exists. Pass --force-negative
+// to explicitly regenerate (e.g. on first creation, or after a normative
+// pin to REJECTION_ERROR_EMBEDDED_KEY changes).
+const negativePath = `${outDir}/cross-verify-embedded-key-bundle.json`;
+let negativeWritten = false;
+if (!existsSync(negativePath) || forceNegative) {
+  writeFileSync(negativePath, JSON.stringify(aps.negative, null, 2) + '\n');
+  negativeWritten = true;
+}
+
+writeFileSync(`${outDir}/keys/aps-ku-cross-verify.jwks`, JSON.stringify(aps.jwks, null, 2) + '\n');
 writeFileSync(
   `${outDir}/selective-disclosure-salted-commit.json`,
   JSON.stringify(sdc, null, 2) + '\n',
@@ -452,5 +554,11 @@ writeFileSync(
 
 console.log('Wrote:');
 console.log(`  ${outDir}/jcs-test-vectors.json (${jcsVecs.vectors.length} cases)`);
-console.log(`  ${outDir}/cross-verify-bundle.json (${bundle.receipts.length} receipts, ${bundle.verification.signing_keys.length} keys)`);
+console.log(`  ${outDir}/cross-verify-bundle.json (${bundle.receipts.length} receipts, ${bundle.verification.signing_keys.length} keys, APS sidecar key)`);
+if (negativeWritten) {
+  console.log(`  ${outDir}/cross-verify-embedded-key-bundle.json (MUST-reject embedded-key fixture${forceNegative ? ', --force-negative' : ', first run'})`);
+} else {
+  console.log(`  ${outDir}/cross-verify-embedded-key-bundle.json (preserved, static; pass --force-negative to regenerate)`);
+}
+console.log(`  ${outDir}/keys/aps-ku-cross-verify.jwks (APS sidecar key)`);
 console.log(`  ${outDir}/selective-disclosure-salted-commit.json (${Object.keys(sdc.witness.disclosures).length} redacted fields)`);
diff --git a/test-vectors/keys/aps-ku-cross-verify.jwks b/test-vectors/keys/aps-ku-cross-verify.jwks
new file mode 100644
index 0000000..f31592f
--- /dev/null
+++ b/test-vectors/keys/aps-ku-cross-verify.jwks
@@ -0,0 +1,13 @@
+{
+  "keys": [
+    {
+      "kty": "OKP",
+      "crv": "Ed25519",
+      "use": "sig",
+      "kid": "aps-ku-cross-verify-v1",
+      "x": "6RxrxbGuAFDbKoTtliVZ6XfMb_TLW9EVdwcb1_pgT6o",
+      "issuer": "aps:test:ku-cross-verify",
+      "seed_note": "derived from sha256(\"aps:veritasacta:ku-cross-verify:v1\") — test key, NOT a production issuer"
+    }
+  ]
+}