diff --git a/src/main/services/team/TeamTaskReader.ts b/src/main/services/team/TeamTaskReader.ts
index 92be5402..fef631a2 100644
--- a/src/main/services/team/TeamTaskReader.ts
+++ b/src/main/services/team/TeamTaskReader.ts
@@ -600,7 +600,7 @@ export class TeamTaskReader {
       const tasks = await request;
       if (TeamTaskReader.allTasksGeneration === generationAtStart) {
         TeamTaskReader.allTasksCache = {
-          value: cloneTasks(tasks),
+          value: tasks,
           expiresAt: Date.now() + ALL_TASKS_CACHE_TTL_MS,
         };
       }
diff --git a/test/main/services/team/TeamTaskReader.test.ts b/test/main/services/team/TeamTaskReader.test.ts
index 27ba1e1a..560ba8f2 100644
--- a/test/main/services/team/TeamTaskReader.test.ts
+++ b/test/main/services/team/TeamTaskReader.test.ts
@@ -92,6 +92,24 @@ describe('TeamTaskReader', () => {
     expect(readAllTasksUncached).toHaveBeenCalledTimes(2);
   });
 
+  it('keeps cached getAllTasks data isolated from caller mutations', async () => {
+    const readAllTasksUncached = vi
+      .spyOn(
+        TeamTaskReader.prototype as unknown as {
+          readAllTasksUncached: () => Promise<(TeamTask & { teamName: string })[]>;
+        },
+        'readAllTasksUncached'
+      )
+      .mockResolvedValueOnce([makeTask('cached-task')]);
+
+    const reader = new TeamTaskReader();
+    const firstRead = await reader.getAllTasks();
+    firstRead[0]!.subject = 'mutated caller copy';
+
+    await expect(reader.getAllTasks()).resolves.toEqual([makeTask('cached-task')]);
+    expect(readAllTasksUncached).toHaveBeenCalledTimes(1);
+  });
+
   it('reuses parsed task files until their file signature changes', async () => {
     await setupTasksRoot();
     await writeTaskFile('atlas-hq', {