diff --git a/server/src/__tests__/issue-stale-execution-lock-routes.test.ts b/server/src/__tests__/issue-stale-execution-lock-routes.test.ts
index ced38bced04..a74ecb1a1c6 100644
--- a/server/src/__tests__/issue-stale-execution-lock-routes.test.ts
+++ b/server/src/__tests__/issue-stale-execution-lock-routes.test.ts
@@ -283,4 +283,65 @@ describeEmbeddedPostgres("stale issue execution lock routes", () => {
       },
     });
   });
+
+  it("self-heals a stale checkoutRunId via clearCheckoutRunIfTerminal on checkout (Fix B path)", async () => {
+    // Reproduces the recurrence pattern: prior owning run died, executionRunId
+    // was cleared by releaseIssueExecutionAndPromote, but checkoutRunId stayed
+    // pinned to the dead run. The new agent's POST /checkout would 409 forever
+    // without the clearCheckoutRunIfTerminal helper in svc.checkout.
+    const { companyId, agentId, failedRunId, currentRunId } = await seedCompanyAgentAndRuns();
+    const issueId = randomUUID();
+    const otherAgentId = randomUUID();
+    await db.insert(agents).values({
+      id: otherAgentId,
+      companyId,
+      name: "OtherAgent",
+      role: "engineer",
+      status: "active",
+      adapterType: "codex_local",
+      adapterConfig: {},
+      runtimeConfig: {},
+      permissions: {},
+    });
+    await db.insert(issues).values({
+      id: issueId,
+      companyId,
+      title: "Stale checkout lock after reassignment",
+      // Status off in_progress + checkoutRunId still set — adoptStaleCheckoutRun
+      // cannot recover from this; only clearCheckoutRunIfTerminal can.
+      status: "todo",
+      priority: "high",
+      assigneeAgentId: otherAgentId,
+      checkoutRunId: failedRunId,
+      executionRunId: null,
+      executionAgentNameKey: null,
+      executionLockedAt: null,
+    });
+
+    const res = await request(createApp(agentActor(companyId, otherAgentId, currentRunId)))
+      .post(`/api/issues/${issueId}/checkout`)
+      .send({
+        agentId: otherAgentId,
+        expectedStatuses: ["todo", "backlog", "blocked", "in_review"],
+      });
+
+    expect(res.status, JSON.stringify(res.body)).toBe(200);
+
+    const row = await db
+      .select({
+        status: issues.status,
+        assigneeAgentId: issues.assigneeAgentId,
+        checkoutRunId: issues.checkoutRunId,
+        executionRunId: issues.executionRunId,
+      })
+      .from(issues)
+      .where(eq(issues.id, issueId))
+      .then((rows) => rows[0]);
+    expect(row).toEqual({
+      status: "in_progress",
+      assigneeAgentId: otherAgentId,
+      checkoutRunId: currentRunId,
+      executionRunId: currentRunId,
+    });
+  });
 });
diff --git a/server/src/__tests__/recovery-stale-issue-lock-sweep.test.ts b/server/src/__tests__/recovery-stale-issue-lock-sweep.test.ts
new file mode 100644
index 00000000000..de6baf9016b
--- /dev/null
+++ b/server/src/__tests__/recovery-stale-issue-lock-sweep.test.ts
@@ -0,0 +1,226 @@
+import { randomUUID } from "node:crypto";
+import { eq } from "drizzle-orm";
+import { afterAll, afterEach, beforeAll, describe, expect, it, vi } from "vitest";
+import {
+  activityLog,
+  agents,
+  companies,
+  createDb,
+  heartbeatRuns,
+  issueComments,
+  issueRelations,
+  issues,
+} from "@paperclipai/db";
+import {
+  getEmbeddedPostgresTestSupport,
+  startEmbeddedPostgresTestDatabase,
+} from "./helpers/embedded-postgres.js";
+
+const mockTelemetryClient = vi.hoisted(() => ({ track: vi.fn() }));
+vi.mock("../telemetry.ts", () => ({ getTelemetryClient: () => mockTelemetryClient }));
+
+import { heartbeatService } from "../services/heartbeat.ts";
+
+const embeddedPostgresSupport = await getEmbeddedPostgresTestSupport();
+const describeEmbeddedPostgres = embeddedPostgresSupport.supported ? describe : describe.skip;
+
+if (!embeddedPostgresSupport.supported) {
+  console.warn(
+    `Skipping embedded Postgres stale-lock sweeper tests on this host: ${
+      embeddedPostgresSupport.reason ?? "unsupported environment"
+    }`,
+  );
+}
+
+describeEmbeddedPostgres("recovery sweepStaleIssueLocks", () => {
+  let db!: ReturnType<typeof createDb>;
+  let tempDb: Awaited<ReturnType<typeof startEmbeddedPostgresTestDatabase>> | null = null;
+
+  beforeAll(async () => {
+    tempDb = await startEmbeddedPostgresTestDatabase("paperclip-stale-lock-sweep-");
+    db = createDb(tempDb.connectionString);
+  }, 20_000);
+
+  afterEach(async () => {
+    await db.delete(issueComments);
+    await db.delete(issueRelations);
+    await db.delete(activityLog);
+    await db.delete(issues);
+    await db.delete(heartbeatRuns);
+    await db.delete(agents);
+    await db.delete(companies);
+  });
+
+  afterAll(async () => {
+    await tempDb?.cleanup();
+  });
+
+  async function seed() {
+    const companyId = randomUUID();
+    const agentId = randomUUID();
+    const failedRunId = randomUUID();
+    const runningRunId = randomUUID();
+
+    await db.insert(companies).values({
+      id: companyId,
+      name: "Paperclip",
+      issuePrefix: `T${companyId.replace(/-/g, "").slice(0, 6).toUpperCase()}`,
+      requireBoardApprovalForNewAgents: false,
+    });
+    await db.insert(agents).values({
+      id: agentId,
+      companyId,
+      name: "Coder",
+      role: "engineer",
+      status: "active",
+      adapterType: "codex_local",
+      adapterConfig: {},
+      runtimeConfig: {},
+      permissions: {},
+    });
+    await db.insert(heartbeatRuns).values([
+      {
+        id: failedRunId,
+        companyId,
+        agentId,
+        status: "failed",
+        invocationSource: "manual",
+        finishedAt: new Date(),
+      },
+      {
+        id: runningRunId,
+        companyId,
+        agentId,
+        status: "running",
+        invocationSource: "manual",
+        startedAt: new Date(),
+      },
+    ]);
+
+    return { companyId, agentId, failedRunId, runningRunId };
+  }
+
+  it("clears lock columns when checkoutRunId points at a terminal heartbeat run", async () => {
+    const { companyId, agentId, failedRunId } = await seed();
+    const issueId = randomUUID();
+    await db.insert(issues).values({
+      id: issueId,
+      companyId,
+      title: "Stale lock — terminal checkoutRunId",
+      // Status off in_progress + checkoutRunId still set → exactly the recurrence shape.
+      status: "todo",
+      priority: "high",
+      assigneeAgentId: agentId,
+      checkoutRunId: failedRunId,
+      executionRunId: null,
+    });
+
+    const heartbeat = heartbeatService(db);
+    const result = await heartbeat.sweepStaleIssueLocks();
+
+    expect(result.cleared).toBe(1);
+    expect(result.issueIds).toEqual([issueId]);
+
+    const row = await db
+      .select({
+        checkoutRunId: issues.checkoutRunId,
+        executionRunId: issues.executionRunId,
+        executionLockedAt: issues.executionLockedAt,
+      })
+      .from(issues)
+      .where(eq(issues.id, issueId))
+      .then((rows) => rows[0]);
+    expect(row).toEqual({ checkoutRunId: null, executionRunId: null, executionLockedAt: null });
+
+    const audit = await db
+      .select({ action: activityLog.action, details: activityLog.details })
+      .from(activityLog)
+      .where(eq(activityLog.action, "issue.stale_lock_cleared"))
+      .then((rows) => rows[0]);
+    expect(audit?.action).toBe("issue.stale_lock_cleared");
+    expect((audit?.details as { clearedCheckoutRunId?: string } | null)?.clearedCheckoutRunId).toBe(
+      failedRunId,
+    );
+  });
+
+  it("does not clear locks while the referenced run is still running", async () => {
+    const { companyId, agentId, runningRunId } = await seed();
+    const issueId = randomUUID();
+    await db.insert(issues).values({
+      id: issueId,
+      companyId,
+      title: "Live lock — must be preserved",
+      status: "in_progress",
+      priority: "high",
+      assigneeAgentId: agentId,
+      checkoutRunId: runningRunId,
+      executionRunId: runningRunId,
+      executionLockedAt: new Date(),
+    });
+
+    const heartbeat = heartbeatService(db);
+    const result = await heartbeat.sweepStaleIssueLocks();
+
+    expect(result.cleared).toBe(0);
+    const row = await db
+      .select({
+        checkoutRunId: issues.checkoutRunId,
+        executionRunId: issues.executionRunId,
+      })
+      .from(issues)
+      .where(eq(issues.id, issueId))
+      .then((rows) => rows[0]);
+    expect(row).toEqual({ checkoutRunId: runningRunId, executionRunId: runningRunId });
+  });
+
+  it("does not clear when checkoutRunId is terminal but executionRunId is still running", async () => {
+    const { companyId, agentId, failedRunId, runningRunId } = await seed();
+    const issueId = randomUUID();
+    await db.insert(issues).values({
+      id: issueId,
+      companyId,
+      title: "Mixed lock — preserve",
+      status: "in_progress",
+      priority: "high",
+      assigneeAgentId: agentId,
+      checkoutRunId: failedRunId,
+      executionRunId: runningRunId,
+      executionLockedAt: new Date(),
+    });
+
+    const heartbeat = heartbeatService(db);
+    const result = await heartbeat.sweepStaleIssueLocks();
+
+    expect(result.cleared).toBe(0);
+    const row = await db
+      .select({
+        checkoutRunId: issues.checkoutRunId,
+        executionRunId: issues.executionRunId,
+      })
+      .from(issues)
+      .where(eq(issues.id, issueId))
+      .then((rows) => rows[0]);
+    expect(row).toEqual({ checkoutRunId: failedRunId, executionRunId: runningRunId });
+  });
+
+  it("is idempotent — second pass finds nothing to clear", async () => {
+    const { companyId, agentId, failedRunId } = await seed();
+    const issueId = randomUUID();
+    await db.insert(issues).values({
+      id: issueId,
+      companyId,
+      title: "Idempotency",
+      status: "todo",
+      priority: "high",
+      assigneeAgentId: agentId,
+      checkoutRunId: failedRunId,
+      executionRunId: null,
+    });
+
+    const heartbeat = heartbeatService(db);
+    const first = await heartbeat.sweepStaleIssueLocks();
+    const second = await heartbeat.sweepStaleIssueLocks();
+    expect(first.cleared).toBe(1);
+    expect(second.cleared).toBe(0);
+  });
+});
diff --git a/server/src/index.ts b/server/src/index.ts
index 105f23ecaf7..9180849c17c 100644
--- a/server/src/index.ts
+++ b/server/src/index.ts
@@ -707,6 +707,12 @@ export async function startServer(): Promise<StartedServer> {
           logger.warn({ ...scanned }, "startup active-run output watchdog created review work");
         }
       })
+      .then(async () => {
+        const swept = await heartbeat.sweepStaleIssueLocks();
+        if (swept.cleared > 0) {
+          logger.warn({ ...swept }, "startup stale-lock sweeper cleared issue locks");
+        }
+      })
       .then(async () => {
         const reviewed = await heartbeat.reconcileProductivityReviews();
         if (reviewed.created > 0 || reviewed.updated > 0 || reviewed.failed > 0) {
@@ -773,6 +779,12 @@ export async function startServer(): Promise<StartedServer> {
             logger.warn({ ...scanned }, "periodic active-run output watchdog created review work");
           }
         })
+        .then(async () => {
+          const swept = await heartbeat.sweepStaleIssueLocks();
+          if (swept.cleared > 0) {
+            logger.warn({ ...swept }, "periodic stale-lock sweeper cleared issue locks");
+          }
+        })
         .then(async () => {
           const reviewed = await heartbeat.reconcileProductivityReviews();
           if (reviewed.created > 0 || reviewed.updated > 0 || reviewed.failed > 0) {
diff --git a/server/src/services/heartbeat.ts b/server/src/services/heartbeat.ts
index 3fa574b7783..9728466d145 100644
--- a/server/src/services/heartbeat.ts
+++ b/server/src/services/heartbeat.ts
@@ -6593,6 +6593,10 @@ export function heartbeatService(db: Db, options: HeartbeatServiceOptions = {})
     return recovery.reconcileStrandedAssignedIssues();
   }
 
+  async function sweepStaleIssueLocks() {
+    return recovery.sweepStaleIssueLocks();
+  }
+
   function issueIdFromRunContext(contextSnapshot: unknown) {
     const context = parseObject(contextSnapshot);
     return readNonEmptyString(context.issueId) ?? readNonEmptyString(context.taskId);
@@ -8158,16 +8162,26 @@ export function heartbeatService(db: Db, options: HeartbeatServiceOptions = {})
       if (!issue) return null;
       if (issue.executionRunId && issue.executionRunId !== run.id) return null;
 
-      if (issue.executionRunId === run.id) {
+      // Clear lock columns that point at the terminating run. checkoutRunId is
+      // cleared here in addition to executionRunId so the issue self-heals even
+      // if its assignee or status changed between checkout and termination —
+      // adoptStaleCheckoutRun's narrow WHERE clause cannot cover those paths.
+      if (issue.executionRunId === run.id || issue.checkoutRunId === run.id) {
         await tx
           .update(issues)
           .set({
+            checkoutRunId: null,
             executionRunId: null,
             executionAgentNameKey: null,
             executionLockedAt: null,
             updatedAt: new Date(),
           })
-          .where(eq(issues.id, issue.id));
+          .where(
+            and(
+              eq(issues.id, issue.id),
+              or(eq(issues.executionRunId, run.id), eq(issues.checkoutRunId, run.id)),
+            ),
+          );
       }
 
       while (true) {
@@ -9719,6 +9733,8 @@ export function heartbeatService(db: Db, options: HeartbeatServiceOptions = {})
 
     reconcileStrandedAssignedIssues,
 
+    sweepStaleIssueLocks,
+
     buildIssueGraphLivenessAutoRecoveryPreview,
 
     reconcileIssueGraphLiveness,
diff --git a/server/src/services/issues.ts b/server/src/services/issues.ts
index fb47582fe04..e0839371d59 100644
--- a/server/src/services/issues.ts
+++ b/server/src/services/issues.ts
@@ -3382,8 +3382,58 @@ export function issueService(db: Db) {
     });
   }
 
+  // Symmetric to clearExecutionRunIfTerminal. Clears checkoutRunId (and the
+  // bundled execution lock cols) when the row's checkoutRunId points at a
+  // heartbeat run that is terminal or no longer exists. No assignee/status
+  // precondition: a terminal run holds no real claim regardless of who is
+  // assigned or what status the issue is currently in.
+  async function clearCheckoutRunIfTerminal(issueId: string): Promise<boolean> {
+    return db.transaction(async (tx) => {
+      await tx.execute(
+        sql`select ${issues.id} from ${issues} where ${issues.id} = ${issueId} for update`,
+      );
+      const issue = await tx
+        .select({ checkoutRunId: issues.checkoutRunId })
+        .from(issues)
+        .where(eq(issues.id, issueId))
+        .then((rows) => rows[0] ?? null);
+      if (!issue?.checkoutRunId) return false;
+
+      await tx.execute(
+        sql`select ${heartbeatRuns.id} from ${heartbeatRuns} where ${heartbeatRuns.id} = ${issue.checkoutRunId} for update`,
+      );
+      const run = await tx
+        .select({ status: heartbeatRuns.status })
+        .from(heartbeatRuns)
+        .where(eq(heartbeatRuns.id, issue.checkoutRunId))
+        .then((rows) => rows[0] ?? null);
+      if (run && !TERMINAL_HEARTBEAT_RUN_STATUSES.has(run.status)) return false;
+
+      const updated = await tx
+        .update(issues)
+        .set({
+          checkoutRunId: null,
+          executionRunId: null,
+          executionAgentNameKey: null,
+          executionLockedAt: null,
+          updatedAt: new Date(),
+        })
+        .where(
+          and(
+            eq(issues.id, issueId),
+            eq(issues.checkoutRunId, issue.checkoutRunId),
+          ),
+        )
+        .returning({ id: issues.id })
+        .then((rows) => rows[0] ?? null);
+
+      return Boolean(updated);
+    });
+  }
+
   return {
     clearExecutionRunIfTerminal,
+    clearCheckoutRunIfTerminal,
 
     list: async (companyId: string, filters?: IssueFilters) => {
       if (filters?.attention === "blocked") {
@@ -4610,6 +4660,7 @@ export function issueService(db: Db) {
       }
 
       await clearExecutionRunIfTerminal(id);
+      await clearCheckoutRunIfTerminal(id);
 
       const dependencyReadiness = await listIssueDependencyReadinessMap(db, issueCompany.companyId, [id]);
       const unresolvedBlockerIssueIds = dependencyReadiness.get(id)?.unresolvedBlockerIssueIds ?? [];
@@ -4739,6 +4790,7 @@ export function issueService(db: Db) {
 
     assertCheckoutOwner: async (id: string, actorAgentId: string, actorRunId: string | null) => {
       await clearExecutionRunIfTerminal(id);
+      await clearCheckoutRunIfTerminal(id);
       const current = await db
         .select({
           id: issues.id,
@@ -4817,6 +4869,7 @@ export function issueService(db: Db) {
 
     release: async (id: string, actorAgentId?: string, actorRunId?: string | null) => {
       await clearExecutionRunIfTerminal(id);
+      await clearCheckoutRunIfTerminal(id);
       const existing = await db
         .select()
         .from(issues)
diff --git a/server/src/services/recovery/service.ts b/server/src/services/recovery/service.ts
index f94d5b52c0a..341b444f125 100644
--- a/server/src/services/recovery/service.ts
+++ b/server/src/services/recovery/service.ts
@@ -3039,6 +3039,112 @@ export function recoveryService(db: Db, deps: { enqueueWakeup: RecoveryWakeup })
     return Math.max(1, Math.floor(asNumber(raw, fallback)));
   }
 
+  // Backstop sweeper: clears stale lock columns on issues whose checkoutRunId
+  // or executionRunId points at a heartbeat_runs row that is either missing or
+  // in a terminal status. Provides self-heal for stale locks that fell outside
+  // releaseIssueExecutionAndPromote / clearCheckoutRunIfTerminal / adoption.
+  // Idempotent and safe: clears at most one row's worth of lock columns per
+  // candidate, and only when the referenced run row is unambiguously terminal.
+  async function sweepStaleIssueLocks() {
+    const TERMINAL_STATUSES = ["succeeded", "failed", "cancelled", "timed_out"] as const;
+    const result = {
+      cleared: 0,
+      issueIds: [] as string[],
+    };
+
+    const candidates = await db
+      .select({
+        id: issues.id,
+        companyId: issues.companyId,
+        checkoutRunId: issues.checkoutRunId,
+        executionRunId: issues.executionRunId,
+      })
+      .from(issues)
+      .where(
+        sql`(${issues.checkoutRunId} is not null or ${issues.executionRunId} is not null)`,
+      );
+
+    for (const issue of candidates) {
+      const referencedRunIds = [issue.checkoutRunId, issue.executionRunId].filter(
+        (id): id is string => !!id,
+      );
+      if (referencedRunIds.length === 0) continue;
+
+      const runRows = await db
+        .select({ id: heartbeatRuns.id, status: heartbeatRuns.status })
+        .from(heartbeatRuns)
+        .where(inArray(heartbeatRuns.id, referencedRunIds));
+
+      const runStatusById = new Map<string, string>();
+      for (const row of runRows) runStatusById.set(row.id, row.status);
+
+      const isCleanable = (runId: string | null) => {
+        if (!runId) return true;
+        const status = runStatusById.get(runId);
+        if (!status) return true; // missing run row → no real claim
+        return (TERMINAL_STATUSES as readonly string[]).includes(status);
+      };
+
+      if (!isCleanable(issue.checkoutRunId) || !isCleanable(issue.executionRunId)) {
+        continue;
+      }
+
+      const updated = await db
+        .update(issues)
+        .set({
+          checkoutRunId: null,
+          executionRunId: null,
+          executionAgentNameKey: null,
+          executionLockedAt: null,
+          updatedAt: new Date(),
+        })
+        .where(
+          and(
+            eq(issues.id, issue.id),
+            issue.checkoutRunId
+              ? eq(issues.checkoutRunId, issue.checkoutRunId)
+              : isNull(issues.checkoutRunId),
+            issue.executionRunId
+              ? eq(issues.executionRunId, issue.executionRunId)
+              : isNull(issues.executionRunId),
+          ),
+        )
+        .returning({ id: issues.id })
+        .then((rows) => rows[0] ?? null);
+
+      if (!updated) continue;
+
+      result.cleared += 1;
+      result.issueIds.push(updated.id);
+
+      await logActivity(db, {
+        companyId: issue.companyId,
+        actorType: "system",
+        actorId: "system",
+        agentId: null,
+        runId: null,
+        action: "issue.stale_lock_cleared",
+        entityType: "issue",
+        entityId: updated.id,
+        details: {
+          source: "recovery.sweep_stale_issue_locks",
+          clearedCheckoutRunId: issue.checkoutRunId,
+          clearedExecutionRunId: issue.executionRunId,
+          referencedRunStatuses: Object.fromEntries(runStatusById),
+        },
+      });
+    }
+
+    if (result.cleared > 0) {
+      logger.warn(
+        { cleared: result.cleared, issueIds: result.issueIds },
+        "swept stale issue lock columns",
+      );
+    }
+
+    return result;
+  }
+
   return {
     buildRunOutputSilence,
     escalateStrandedRecoveryIssueInPlace,
@@ -3046,6 +3152,7 @@ export function recoveryService(db: Db, deps: { enqueueWakeup: RecoveryWakeup })
     recordWatchdogDecision,
     scanSilentActiveRuns,
     reconcileStrandedAssignedIssues,
+    sweepStaleIssueLocks,
     buildIssueGraphLivenessAutoRecoveryPreview,
     reconcileIssueGraphLiveness,
     readRecoveryTimerIntervalMs,