diff --git a/src/resources/extensions/gsd/auto.ts b/src/resources/extensions/gsd/auto.ts
index be8a5c2d30..0f6ff98309 100644
--- a/src/resources/extensions/gsd/auto.ts
+++ b/src/resources/extensions/gsd/auto.ts
@@ -299,7 +299,11 @@ export type {
 import { autoSession as s } from "./auto-runtime-state.js";
 import { gsdHome } from "./gsd-home.js";
 import { createWorkspace, scopeMilestone } from "./workspace.js";
-import { registerAutoWorker, markWorkerStopping } from "./db/auto-workers.js";
+import {
+  registerAutoWorker,
+  markWorkerStopping,
+  markWorkerStoppingByPid,
+} from "./db/auto-workers.js";
 import { releaseMilestoneLease } from "./db/milestone-leases.js";
 import { normalizeRealPath } from "./paths.js";
 
@@ -919,6 +923,7 @@ export function checkRemoteAutoSession(projectRoot: string): {
 
   if (!isLockProcessAlive(lock)) {
     // Stale lock from a dead process — not a live remote session
+    markWorkerStoppingByPid(normalizeRealPath(projectRoot), lock.pid);
     return { running: false };
   }
 
diff --git a/src/resources/extensions/gsd/crash-recovery.ts b/src/resources/extensions/gsd/crash-recovery.ts
index d77b807a8b..e4996e7f3e 100644
--- a/src/resources/extensions/gsd/crash-recovery.ts
+++ b/src/resources/extensions/gsd/crash-recovery.ts
@@ -32,6 +32,7 @@ import {
   getAllAutoWorkers,
   markWorkerCrashed,
   markWorkerStopping,
+  markWorkerStoppingByPid,
   type AutoWorkerRow,
 } from "./db/auto-workers.js";
 import { forceReleaseLeasesForWorker } from "./db/milestone-leases.js";
@@ -234,6 +235,8 @@ export function clearLock(basePath: string): void {
       deleteRuntimeKv("worker", staleWorker.worker_id, SESSION_FILE_KV_KEY);
       return;
     }
+    const lock = readLegacyLock(basePath);
+    if (lock?.pid) markWorkerStoppingByPid(projectRoot, lock.pid);
     const worker = findActiveWorkerForCurrentProcess(projectRoot);
     if (worker) deleteRuntimeKv("worker", worker.worker_id, SESSION_FILE_KV_KEY);
 
diff --git a/src/resources/extensions/gsd/db/auto-workers.ts b/src/resources/extensions/gsd/db/auto-workers.ts
index 263e0a5984..0bf6508d0a 100644
--- a/src/resources/extensions/gsd/db/auto-workers.ts
+++ b/src/resources/extensions/gsd/db/auto-workers.ts
@@ -157,6 +157,31 @@ export function markWorkerStopping(workerId: string): void {
   });
 }
 
+/**
+ * Mark the active worker row for a specific PID/project root as stopping.
+ * Used when we detect a dead PID from lock metadata before heartbeat expiry.
+ */
+export function markWorkerStoppingByPid(
+  projectRootRealpath: string,
+  pid: number,
+): void {
+  if (!isDbAvailable()) return;
+  if (!Number.isInteger(pid) || pid <= 0) return;
+  const db = _getAdapter()!;
+  transaction(() => {
+    db.prepare(
+      `UPDATE workers
+       SET status = 'stopping'
+       WHERE pid = :pid
+         AND project_root_realpath = :project_root
+         AND status = 'active'`,
+    ).run({
+      ":pid": pid,
+      ":project_root": projectRootRealpath,
+    });
+  });
+}
+
 /**
  * Return all workers whose status is 'active' AND whose heartbeat is within
  * the TTL window. Workers older than the TTL are NOT auto-marked crashed
diff --git a/src/resources/extensions/gsd/session-lock.ts b/src/resources/extensions/gsd/session-lock.ts
index d392d2e59a..72ca8af500 100644
--- a/src/resources/extensions/gsd/session-lock.ts
+++ b/src/resources/extensions/gsd/session-lock.ts
@@ -19,8 +19,9 @@
 import { createRequire } from "node:module";
 import { existsSync, readFileSync, readdirSync, mkdirSync, unlinkSync, rmSync, statSync } from "node:fs";
 import { join, dirname } from "node:path";
-import { gsdRoot } from "./paths.js";
+import { gsdRoot, normalizeRealPath } from "./paths.js";
 import { atomicWriteSync } from "./atomic-write.js";
+import { markWorkerStoppingByPid } from "./db/auto-workers.js";
 
 const _require = createRequire(import.meta.url);
 
@@ -281,6 +282,13 @@ export function acquireSessionLock(basePath: string): SessionLockResult {
   // Clean up numbered lock file variants from cloud sync conflicts (#1315)
   cleanupStrayLockFiles(basePath);
 
+  // If lock metadata points to a dead PID, mark that worker row stopping so
+  // crash diagnostics do not keep surfacing it as active.
+  const existingPreflight = readExistingLockData(lp);
+  if (existingPreflight?.pid && !isPidAlive(existingPreflight.pid)) {
+    markWorkerStoppingByPid(normalizeRealPath(basePath), existingPreflight.pid);
+  }
+
   // Write our lock data first (the content is informational; the OS lock is the real guard)
   const lockData: SessionLockData = {
     pid: process.pid,
@@ -308,7 +316,9 @@ export function acquireSessionLock(basePath: string): SessionLockResult {
   const lockDir = lockTarget + ".lock";
   if (existsSync(lockDir)) {
     const existingData = readExistingLockData(lp);
-    const isOrphan = !existingData || (existingData.pid && !isPidAlive(existingData.pid));
+    const deadPid = existingData?.pid && !isPidAlive(existingData.pid) ? existingData.pid : null;
+    if (deadPid) markWorkerStoppingByPid(normalizeRealPath(basePath), deadPid);
+    const isOrphan = !existingData || !!deadPid;
     if (isOrphan) {
       try { rmSync(lockDir, { recursive: true, force: true }); } catch { /* best-effort */ }
       try { if (existsSync(lp)) unlinkSync(lp); } catch { /* best-effort */ }
@@ -344,6 +354,9 @@ export function acquireSessionLock(basePath: string): SessionLockResult {
     // Check: if auto.lock is gone and no process is alive, the lock dir is stale.
     const existingData = readExistingLockData(lp);
     const existingPid = existingData?.pid;
+    if (existingPid && !isPidAlive(existingPid)) {
+      markWorkerStoppingByPid(normalizeRealPath(basePath), existingPid);
+    }
 
     // If no lock file or no alive process, try to clean up and re-acquire (#1245)
     if (!existingData || (existingPid && !isPidAlive(existingPid))) {
diff --git a/src/resources/extensions/gsd/tests/auto-workers.test.ts b/src/resources/extensions/gsd/tests/auto-workers.test.ts
index c9c896d259..c265c3dad7 100644
--- a/src/resources/extensions/gsd/tests/auto-workers.test.ts
+++ b/src/resources/extensions/gsd/tests/auto-workers.test.ts
@@ -13,6 +13,7 @@ import {
   heartbeatAutoWorker,
   markWorkerCrashed,
   markWorkerStopping,
+  markWorkerStoppingByPid,
   getActiveAutoWorkers,
   getAutoWorker,
 } from "../db/auto-workers.ts";
@@ -71,6 +72,18 @@ test("markWorkerStopping flips status to stopping", (t) => {
   assert.equal(row.status, "stopping");
 });
 
+test("markWorkerStoppingByPid flips matching active row to stopping", (t) => {
+  const base = makeBase();
+  t.after(() => cleanup(base));
+  openDatabase(join(base, ".gsd", "gsd.db"));
+
+  const id = registerAutoWorker({ projectRootRealpath: base });
+  const pid = getAutoWorker(id)!.pid;
+  markWorkerStoppingByPid(base, pid);
+  const row = getAutoWorker(id)!;
+  assert.equal(row.status, "stopping");
+});
+
 test("markWorkerCrashed flips status to crashed", (t) => {
   const base = makeBase();
   t.after(() => cleanup(base));
diff --git a/src/resources/extensions/gsd/tests/session-lock-regression.test.ts b/src/resources/extensions/gsd/tests/session-lock-regression.test.ts
index a494bc3c5a..587949128e 100644
--- a/src/resources/extensions/gsd/tests/session-lock-regression.test.ts
+++ b/src/resources/extensions/gsd/tests/session-lock-regression.test.ts
@@ -25,6 +25,9 @@ import {
   isSessionLockHeld,
 } from '../session-lock.ts';
 import { gsdRoot } from '../paths.ts';
+import { openDatabase, closeDatabase, _getAdapter } from "../gsd-db.ts";
+import { registerAutoWorker, getAutoWorker } from "../db/auto-workers.ts";
+import { normalizeRealPath } from "../paths.ts";
 import { describe, test } from 'node:test';
 import assert from 'node:assert/strict';
 
@@ -94,6 +97,38 @@ describe('session-lock-regression', async () => {
     }
   }
 
+  // ─── 2b. Dead lock PID is marked stopping in workers table ────────────
+  console.log('\n=== 2b. dead lock PID marks worker stopping ===');
+  {
+    const base = mkdtempSync(join(tmpdir(), 'gsd-session-lock-'));
+    mkdirSync(join(base, '.gsd'), { recursive: true });
+
+    try {
+      openDatabase(join(base, ".gsd", "gsd.db"));
+      const projectRoot = normalizeRealPath(base);
+      const workerId = registerAutoWorker({ projectRootRealpath: projectRoot });
+      const deadPid = 99999;
+      writeFileSync(join(gsdRoot(base), "auto.lock"), JSON.stringify({
+        pid: deadPid,
+        startedAt: new Date().toISOString(),
+        unitType: "starting",
+        unitId: "bootstrap",
+        unitStartedAt: new Date().toISOString(),
+      }));
+      // Align worker PID with stale lock metadata.
+      _getAdapter()?.prepare("UPDATE workers SET pid = :pid WHERE worker_id = :id")
+        .run({ ":pid": deadPid, ":id": workerId });
+
+      const result = acquireSessionLock(base);
+      assert.ok(result.acquired, "acquire recovers stale lock");
+      assert.equal(getAutoWorker(workerId)?.status, "stopping");
+      releaseSessionLock(base);
+    } finally {
+      try { closeDatabase(); } catch { /* noop */ }
+      rmSync(base, { recursive: true, force: true });
+    }
+  }
+
   // ─── 3. updateSessionLock preserves lock data ─────────────────────────
   console.log('\n=== 3. updateSessionLock writes metadata ===');
   {