diff --git a/docs/evidence/compact-daily-stock-state-cache-key-20260905.json b/docs/evidence/compact-daily-stock-state-cache-key-20260905.json
new file mode 100644
index 0000000..2bdbda7
--- /dev/null
+++ b/docs/evidence/compact-daily-stock-state-cache-key-20260905.json
@@ -0,0 +1,79 @@
+{
+  "schemaVersion": "fidc-compact-daily-stock-state-cache-key/v1",
+  "measuredAt": "2026-09-05T01:20:00+08:00",
+  "host": "192.168.31.177",
+  "engineCommit": "6f81e1940ad4ddd4eefbe12c056be28f2b64d127",
+  "runnerBinarySha256": "c2d9101a89b71b51051b8762375476518e40d40e29a8ee0f9615ac4c55fcdb0a",
+  "implementation": {
+    "description": "remove the redundant execution date from stock-state cache keys because the complete cache is already cleared before the active date changes",
+    "keyBefore": "(execution_date, factor_date, symbol_id, execution_time, use_intraday_quote)",
+    "keyAfter": "(factor_date, symbol_id, execution_time, use_intraday_quote)",
+    "crossDateResetTested": true,
+    "cachedFactorValues": false,
+    "cachedSelectionResults": false,
+    "pitSemanticsChanged": false
+  },
+  "primaryFiveYearContract": {
+    "startDate": "2021-08-23",
+    "endDate": "2026-08-28",
+    "frequency": "1d",
+    "matchingType": "next_bar_open",
+    "totalReturn": 0.9219861819172002,
+    "tradeCount": 26088,
+    "canonicalSha256": "b42fea66237d06eadb24f6b8c9e2760e7319fe3699f315b99e01f433ef2aa234",
+    "resultStoreSha256": "92343fb369fea68b2544b654151c5c43a935940580b14afbe8eefb3844f72a54",
+    "hotEngineSeconds": [5.262, 5.734, 5.89, 5.612, 6.301],
+    "hotMedianEngineSeconds": 5.734,
+    "sharedOrderBaselineMedianEngineSeconds": 5.742,
+    "observedMedianImprovementPercent": 0.13932427725531174,
+    "resultConsistent": true,
+    "terminalAuditStatus": "clean"
+  },
+  "secondaryFiveYearContract": {
+    "totalReturn": 1.1342962298106998,
+    "tradeCount": 19404,
+    "canonicalSha256": "0dbd3fad624097c673c4a5ec2f545f95e9c21d1d5337bb2b48ffeb22b16cb2b9",
+    "resultStoreSha256": "416d2f87241fb4c6b917f6aeecb588f82f6e7d51a103f4c53a74d11971f16839",
+    "engineSeconds": [5.889, 5.853, 5.342],
+    "medianEngineSeconds": 5.853,
+    "resultConsistent": true,
+    "terminalAuditStatus": "clean"
+  },
+  "coldDataObservation": {
+    "runId": "btr_1788542108713_2936456_0",
+    "totalSeconds": 54.502,
+    "dataSeconds": 46.584,
+    "engineSeconds": 7.011,
+    "sourceQuerySeconds": 17.585,
+    "datasetConstructSeconds": 12.913,
+    "marketIndexBuildSeconds": 7.671,
+    "adjustmentValidationSeconds": 1.855,
+    "hotDataSecondsRange": [0.002, 0.006],
+    "performanceComparisonExcluded": true
+  },
+  "memoryObservation": {
+    "processRssKiB": 11136672,
+    "processAnonymousKiB": 11120428,
+    "cgroupCurrentBytes": 12445237248,
+    "cgroupFileCacheBytes": 1029632000,
+    "cgroupActiveFileBytes": 1009012736,
+    "duplicateDataSetLeakObserved": false,
+    "note": "the gap between process RSS and cgroup memory is reclaimable file-page cache rather than a second resident DataSet"
+  },
+  "testGate": {
+    "coreUnitTotal": 420,
+    "corePassed": 414,
+    "ignoredManualBenchmarks": 6,
+    "failed": 0,
+    "integrationSuitesPassed": true
+  },
+  "remoteArtifacts": [
+    "/srv/fidc/canonical/run/fidc-private/evidence/compact-stock-cache-key-20260905.json",
+    "/srv/fidc/canonical/run/fidc-private/evidence/compact-stock-cache-key-secondary-20260905.json"
+  ],
+  "acceptance": {
+    "status": "accepted_structural_compaction_no_regression",
+    "endToEndSpeedupClaimed": false,
+    "reason": "the key is smaller, the cross-date isolation test passes, both five-year strategies retain exact results, and observed wall time is neutral to slightly better"
+  }
+}