diff --git a/.changeset/coding-ideas-intake-safety.md b/.changeset/coding-ideas-intake-safety.md
index cc6618d2fb..93ad50efbd 100644
--- a/.changeset/coding-ideas-intake-safety.md
+++ b/.changeset/coding-ideas-intake-safety.md
@@ -4,4 +4,4 @@
 
 summary: Ideas-intake cards no longer auto-process on restart; replan and Retry work from Todo; All-workflows shows every card.
 category: fix
-dev: Store init now always runs the workflow-aware integrity pass instead of the retired flag-off evacuation (`evacuateCustomColumnsToLegacy` remains toggle-only), with a mis-mapping guard so stale selections are never physically rehomed into auto-triaged lanes; engine replan/stale-spec/fs-validation rebounds resolve `resolveReplanTargetColumn` instead of hardcoding `triage`; `needs-replan` counts as unplanned for hold-release dispatch; triage discovers `needs-replan` todo cards and refinement seed prompts via `isUnplannedSeedPrompt`/`buildRefinementSeedPrompt`; Board's aggregate grouping renders column-orphaned tasks (hidden columns stay hidden) and the FN-7591 refetch also fires on present-but-unrepresentable mappings.
+dev: Store init records a `store:open` run-audit provenance stamp (pid/ppid/execPath/entry/cwd/node version) so mystery DB mutations are attributable to their process; init also now always runs the workflow-aware integrity pass instead of the retired flag-off evacuation (`evacuateCustomColumnsToLegacy` remains toggle-only), with a mis-mapping guard so stale selections are never physically rehomed into auto-triaged lanes; engine replan/stale-spec/fs-validation rebounds resolve `resolveReplanTargetColumn` instead of hardcoding `triage`; `needs-replan` counts as unplanned for hold-release dispatch; triage discovers `needs-replan` todo cards and refinement seed prompts via `isUnplannedSeedPrompt`/`buildRefinementSeedPrompt`; Board's aggregate grouping renders column-orphaned tasks (hidden columns stay hidden) and the FN-7591 refetch also fires on present-but-unrepresentable mappings.
diff --git a/AGENTS.md b/AGENTS.md
index f56a473da4..b9284a2226 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -221,6 +221,7 @@ Scoped exception (FN-5819): shared-branch-group members (`branchContext.assignme
 
 ### Run Audit
 
+- Store-open provenance: every `TaskStore.init()` emits `store:open` with ids/paths-only metadata (`pid`, `ppid`, `execPath`, `entry`, `cwd`, `nodeVersion`). Purpose: attribute shared-DB mutations to the process that opened the store (the FN-7910 Ideas-evacuation writer was unidentifiable without it). Tests reading unfiltered `runAuditEvents` must filter out `store:open` rather than assert exact counts.
 - FN-7158: agent performance reflections emit `reflection:generated`, `reflection:skipped`, and `reflection:failed` with ids/counts/outcomes-only metadata; never persist reflection prose or prompt text in run-audit.
 - FN-7528: a deterministic, non-LLM post-task performance capture (`AgentReflectionService.captureTaskPerformance`) runs once per completed task and emits `reflection:captured` with ids/counts/outcomes-only metadata (`retryReworkCount?`, `filesTouchedCount?`, `packagesTouchedCount?`, `verificationFileScoped?`, `durationMs?`); never persists `verificationScopeReason` free-text or summary prose in run-audit.
 - FN-7787: `createResolvedAgentSession` enriches `session:runtime-resolved` with `noModelResolved: true` and `runtimeBuiltInFallbackModel` when a non-mock/non-test session reaches runtime creation without a complete provider/model pair; this is a visibility signal for runtime built-in fallback usage, not a fabricated model-resolution verdict.
diff --git a/packages/core/src/__tests__/run-audit.test.ts b/packages/core/src/__tests__/run-audit.test.ts
index 9b093b5a46..2d80330b60 100644
--- a/packages/core/src/__tests__/run-audit.test.ts
+++ b/packages/core/src/__tests__/run-audit.test.ts
@@ -274,7 +274,9 @@ describe("Run Audit", () => {
     });
 
     it("returns all events when no filters provided", () => {
-      const events = store.getRunAuditEvents();
+      // Store init records a `store:open` provenance stamp, so an unfiltered read
+      // returns the five seeded events plus the stamp(s).
+      const events = store.getRunAuditEvents().filter((event) => event.mutationType !== "store:open");
       expect(events).toHaveLength(5);
     });
 
diff --git a/packages/core/src/__tests__/transition-pending-recovery.test.ts b/packages/core/src/__tests__/transition-pending-recovery.test.ts
index 5c79b37ada..7f07291aaf 100644
--- a/packages/core/src/__tests__/transition-pending-recovery.test.ts
+++ b/packages/core/src/__tests__/transition-pending-recovery.test.ts
@@ -215,6 +215,19 @@ describe("#1409 flag ON→OFF evacuation", () => {
       diskStore = new TaskStore(rootDir, globalDir);
       await diskStore.init();
       expect((await diskStore.getTask(task.id)).column).toBe("intake");
+
+      // Store-open provenance stamp: every init records which process opened the
+      // store so mystery mutations (e.g. a stale binary's evacuation) are
+      // attributable after the fact.
+      const stampRows = (diskStore as unknown as {
+        db: { prepare: (s: string) => { all: (...a: unknown[]) => unknown[] } };
+      }).db
+        .prepare(`SELECT metadata FROM runAuditEvents WHERE mutationType = 'store:open'`)
+        .all() as Array<{ metadata: string }>;
+      expect(stampRows.length).toBeGreaterThanOrEqual(2); // first open + reopen
+      const stamp = JSON.parse(stampRows[stampRows.length - 1].metadata) as Record<string, unknown>;
+      expect(stamp.pid).toBe(process.pid);
+      expect(typeof stamp.execPath).toBe("string");
     } finally {
       diskStore.close();
       await rmDir(rootDir, { recursive: true, force: true });
diff --git a/packages/core/src/store.ts b/packages/core/src/store.ts
index 4630455abe..de476f1060 100644
--- a/packages/core/src/store.ts
+++ b/packages/core/src/store.ts
@@ -2086,6 +2086,38 @@ export class TaskStore extends EventEmitter<TaskStoreEvents> {
       });
     }
 
+    /*
+    FNXC:RunAudit 2026-07-13-13:10:
+    Store-open provenance stamp. Every store open runs the init recovery passes below against
+    the SHARED project DB, and a store open by a stale binary is how the FN-7910 incident
+    happened (a pre-fix process's init evacuated Ideas cards; the run-audit row said only
+    agentId:"system", so the writer could not be identified after the fact). Stamp pid /
+    parent pid / executable / entry script / cwd / node version — ids/paths only, no prose —
+    so any future mystery mutation can be attributed to the process that opened the store.
+    Best-effort: a failed stamp never blocks startup.
+    */
+    try {
+      this.insertRunAuditEventRow({
+        agentId: "store",
+        domain: "database",
+        mutationType: "store:open",
+        target: this.rootDir,
+        metadata: {
+          pid: process.pid,
+          ppid: process.ppid,
+          execPath: process.execPath,
+          entry: process.argv[1] ?? null,
+          cwd: process.cwd(),
+          nodeVersion: process.version,
+        },
+      });
+    } catch (err) {
+      storeLog.warn("store-open provenance stamp failed during init", {
+        phase: "init:store-open-stamp",
+        error: err instanceof Error ? err.message : String(err),
+      });
+    }
+
     // U12: workflow-columns integrity pass. Audit + re-home any task whose
     // stored column is no longer valid in its resolved workflow (KTD-1
     // guarantees zero rewrites for healthy legacy rows, so this is a no-op for