diff --git a/server/src/__tests__/issue-update-comment-wakeup-routes.test.ts b/server/src/__tests__/issue-update-comment-wakeup-routes.test.ts
index e7a608cb2e..ce168995c1 100644
--- a/server/src/__tests__/issue-update-comment-wakeup-routes.test.ts
+++ b/server/src/__tests__/issue-update-comment-wakeup-routes.test.ts
@@ -477,6 +477,41 @@ describe("issue update comment wakeups", () => {
     );
   });
 
+  it("does not wake the assignee when a closure comment marks the issue done", async () => {
+    const existing = makeIssue({
+      assigneeAgentId: ASSIGNEE_AGENT_ID,
+      assigneeUserId: null,
+      status: "in_progress",
+    });
+    const updated = {
+      ...existing,
+      status: "done",
+      completedAt: new Date("2026-06-26T16:30:00.000Z"),
+    };
+    mockIssueService.getById.mockResolvedValue(existing);
+    mockIssueService.update.mockResolvedValue(updated);
+    mockIssueService.addComment.mockResolvedValue({
+      id: "comment-close-1",
+      issueId: existing.id,
+      companyId: existing.companyId,
+      body: "Closing this out.",
+    });
+
+    const res = await request(await createApp())
+      .patch(`/api/issues/${existing.id}`)
+      .send({
+        status: "done",
+        comment: "Closing this out.",
+      });
+
+    expect(res.status).toBe(200);
+    await new Promise((resolve) => setImmediate(resolve));
+    const issueCommentedWakeCalls = mockHeartbeatService.wakeup.mock.calls.filter(
+      ([, wakeup]: [string, { reason?: string }]) => wakeup?.reason === "issue_commented",
+    );
+    expect(issueCommentedWakeCalls).toEqual([]);
+  });
+
   it("wakes the assignee on top-level board issue comments", async () => {
     const existing = makeIssue({
       assigneeAgentId: ASSIGNEE_AGENT_ID,
diff --git a/server/src/routes/issues.ts b/server/src/routes/issues.ts
index f2030255d5..694e70490d 100644
--- a/server/src/routes/issues.ts
+++ b/server/src/routes/issues.ts
@@ -9972,7 +9972,10 @@ export function issueRoutes(
         const assigneeId = issue.assigneeAgentId;
         const actorIsAgent = actor.actorType === "agent";
         const selfComment = actorIsAgent && actor.actorId === assigneeId;
-        const skipAssigneeCommentWake = selfComment || isClosed;
+        // Re-derive closed-ness from the post-update issue so a status change
+        // like in_progress -> done with a closure comment does not enqueue a
+        // stale issue_commented wake for an already-completed issue.
+        const skipAssigneeCommentWake = selfComment || isClosedIssueStatus(issue.status);
 
         if (assigneeId && !assigneeChanged && (reopened || !skipAssigneeCommentWake)) {
           addWakeup(assigneeId, {