diff --git a/src/main/services/team/TeamTaskActivityIntervalService.ts b/src/main/services/team/TeamTaskActivityIntervalService.ts
index 3d4765c0..68057def 100644
--- a/src/main/services/team/TeamTaskActivityIntervalService.ts
+++ b/src/main/services/team/TeamTaskActivityIntervalService.ts
@@ -333,6 +333,10 @@ function writeTaskFile(filePath: string, task: MutableTeamTask): void {
 export class TeamTaskActivityIntervalService {
   private readonly resumeMembersCache = new Map<string, ResumeMembersCacheEntry>();
 
+  private getBoardStateLockPath(teamName: string): string {
+    return `${path.join(getTeamsBasePath(), teamName, 'board-state')}.lock`;
+  }
+
   private mutateTeamTasksWithLock(
     teamName: string,
     run: () => ActivityIntervalResult
@@ -520,6 +524,18 @@ export class TeamTaskActivityIntervalService {
     if (memberKeys.size === 0) return { changedTasks: 0 };
     const memberKey = this.makeMemberSetKey(memberKeys);
 
+    const cachedBeforeLock = this.resumeMembersCache.get(teamName);
+    if (cachedBeforeLock?.memberKey === memberKey) {
+      const beforeLockSignature = this.readTaskDirectorySignature(teamName);
+      if (
+        beforeLockSignature &&
+        cachedBeforeLock.signatureKey === beforeLockSignature.key &&
+        !fs.existsSync(this.getBoardStateLockPath(teamName))
+      ) {
+        return { changedTasks: 0 };
+      }
+    }
+
     const result = this.mutateTeamTasksWithLock(teamName, () => {
       const beforeSignature = this.readTaskDirectorySignature(teamName);
       const cached = this.resumeMembersCache.get(teamName);
diff --git a/test/main/services/team/TeamTaskActivityIntervalService.test.ts b/test/main/services/team/TeamTaskActivityIntervalService.test.ts
index a14c6eeb..64ea5f34 100644
--- a/test/main/services/team/TeamTaskActivityIntervalService.test.ts
+++ b/test/main/services/team/TeamTaskActivityIntervalService.test.ts
@@ -547,6 +547,44 @@ describe('TeamTaskActivityIntervalService', () => {
     expect(jsonParseSpy).not.toHaveBeenCalled();
   });
 
+  it('skips the task lock after an unchanged batched resume no-op pass', async () => {
+    await writeTask('alpha', {
+      id: 'bob-task',
+      subject: 'Bob work',
+      owner: 'bob',
+      status: 'in_progress',
+      workIntervals: [{ startedAt: '2026-05-08T10:00:00.000Z' }],
+      historyEvents: [],
+    });
+
+    const service = new TeamTaskActivityIntervalService();
+    expect(
+      service.resumeActiveIntervalsForMembers(
+        'alpha',
+        ['bob'],
+        '2026-05-08T10:20:00.000Z'
+      ).changedTasks
+    ).toBe(0);
+
+    const mutateWithLockSpy = vi.spyOn(
+      TeamTaskActivityIntervalService.prototype as unknown as {
+        mutateTeamTasksWithLock: (
+          teamName: string,
+          run: () => { changedTasks: number; failed?: boolean }
+        ) => { changedTasks: number; failed?: boolean };
+      },
+      'mutateTeamTasksWithLock'
+    );
+    const secondResult = service.resumeActiveIntervalsForMembers(
+      'alpha',
+      ['bob'],
+      '2026-05-08T10:25:00.000Z'
+    );
+
+    expect(secondResult.changedTasks).toBe(0);
+    expect(mutateWithLockSpy).not.toHaveBeenCalled();
+  });
+
   it('refreshes batched resume cache when a task file changes', async () => {
     await writeTask('alpha', {
       id: 'bob-task',