diff --git a/packages/engine/src/__tests__/executor-test-helpers.ts b/packages/engine/src/__tests__/executor-test-helpers.ts
index 46ee963f0..410ab7b91 100644
--- a/packages/engine/src/__tests__/executor-test-helpers.ts
+++ b/packages/engine/src/__tests__/executor-test-helpers.ts
@@ -109,8 +109,12 @@ vi.mock("../worktree-names.js", async () => {
 });
 vi.mock("../worktree-pool.js", async (importOriginal) => {
   const actual = await importOriginal<typeof import("../worktree-pool.js")>();
+  const backend = await vi.importActual<typeof import("../worktree-backend.js")>("../worktree-backend.js");
   return {
     ...actual,
+    ActiveSessionWorktreeRemovalError: backend.ActiveSessionWorktreeRemovalError,
+    RemovalReason: backend.RemovalReason,
+    removeWorktree: vi.fn(actual.removeWorktree),
     classifyTaskWorktree: vi.fn().mockResolvedValue({ ok: true }),
     describeRegisteredWorktrees: vi.fn().mockResolvedValue({ rawOutput: "", canonicalized: [] }),
     isUsableTaskWorktree: vi.fn().mockResolvedValue(true),
diff --git a/packages/engine/src/__tests__/executor-worktree-conflict.test.ts b/packages/engine/src/__tests__/executor-worktree-conflict.test.ts
new file mode 100644
index 000000000..cc62323fe
--- /dev/null
+++ b/packages/engine/src/__tests__/executor-worktree-conflict.test.ts
@@ -0,0 +1,104 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import "./executor-test-helpers.js";
+import { TaskExecutor } from "../executor.js";
+import { activeSessionRegistry } from "../active-session-registry.js";
+import { ActiveSessionWorktreeRemovalError } from "../worktree-backend.js";
+import * as worktreePoolModule from "../worktree-pool.js";
+import { createMockStore, resetExecutorMocks } from "./executor-test-helpers.js";
+
+const CONFLICT_PATH = "/tmp/test/.worktrees/stale-self-owned";
+
+describe("FN-4973: executor worktree conflict cleanup", () => {
+  beforeEach(() => {
+    resetExecutorMocks();
+    activeSessionRegistry.clear();
+  });
+
+  it("reconciles stale self-owned registry entry before removal", async () => {
+    const store = createMockStore();
+    const executor = new TaskExecutor(store, "/tmp/test");
+    store.listTasks.mockResolvedValue([]);
+    activeSessionRegistry.registerPath(CONFLICT_PATH, { taskId: "FN-4973", kind: "executor", ownerKey: "FN-4973" });
+
+    const removeSpy = vi.spyOn(worktreePoolModule, "removeWorktree").mockResolvedValue(undefined);
+    const result = await (executor as any).cleanupConflictingWorktree(CONFLICT_PATH, "fusion/fn-4973", "FN-4973");
+
+    expect(result).toBe(true);
+    expect(removeSpy).toHaveBeenCalled();
+    expect(activeSessionRegistry.lookupByPath(CONFLICT_PATH)).toBeNull();
+    expect(store.logEntry).toHaveBeenCalledWith(
+      "FN-4973",
+      "Reconciled stale self-owned active-session registration",
+      CONFLICT_PATH,
+    );
+  });
+
+  it("does not reconcile when same-task in-memory binding is live and refuses removal", async () => {
+    const store = createMockStore();
+    const executor = new TaskExecutor(store, "/tmp/test");
+    store.listTasks.mockResolvedValue([]);
+    (executor as any).activeWorktrees.set("FN-4973", CONFLICT_PATH);
+    activeSessionRegistry.registerPath(CONFLICT_PATH, { taskId: "FN-4973", kind: "executor", ownerKey: "FN-4973" });
+
+    vi.spyOn(worktreePoolModule, "removeWorktree").mockRejectedValue(
+      new ActiveSessionWorktreeRemovalError({
+        worktreePath: CONFLICT_PATH,
+        taskId: "FN-4973",
+        kind: "executor",
+        ownerKey: "FN-4973",
+        reason: worktreePoolModule.RemovalReason.ExecutorDispose,
+      }),
+    );
+
+    const result = await (executor as any).cleanupConflictingWorktree(CONFLICT_PATH, "fusion/fn-4973", "FN-4973");
+    expect(result).toBe(false);
+    expect(activeSessionRegistry.lookupByPath(CONFLICT_PATH)?.taskId).toBe("FN-4973");
+  });
+
+  it("does not reconcile foreign-task registry entries and keeps refusal behavior", async () => {
+    const store = createMockStore();
+    const executor = new TaskExecutor(store, "/tmp/test");
+    store.listTasks.mockResolvedValue([]);
+    activeSessionRegistry.registerPath(CONFLICT_PATH, { taskId: "FN-OTHER", kind: "executor", ownerKey: "FN-OTHER" });
+
+    vi.spyOn(worktreePoolModule, "removeWorktree").mockRejectedValue(
+      new ActiveSessionWorktreeRemovalError({
+        worktreePath: CONFLICT_PATH,
+        taskId: "FN-OTHER",
+        kind: "executor",
+        ownerKey: "FN-OTHER",
+        reason: worktreePoolModule.RemovalReason.ExecutorDispose,
+      }),
+    );
+
+    const result = await (executor as any).cleanupConflictingWorktree(CONFLICT_PATH, "fusion/fn-4973", "FN-4973");
+    expect(result).toBe(false);
+    expect(activeSessionRegistry.lookupByPath(CONFLICT_PATH)?.taskId).toBe("FN-OTHER");
+  });
+
+  it("reconciles once on race-window ActiveSessionWorktreeRemovalError then retries removal", async () => {
+    const store = createMockStore();
+    const executor = new TaskExecutor(store, "/tmp/test");
+    store.listTasks.mockResolvedValue([]);
+
+    const removeSpy = vi.spyOn(worktreePoolModule, "removeWorktree");
+    removeSpy
+      .mockImplementationOnce(async () => {
+        activeSessionRegistry.registerPath(CONFLICT_PATH, { taskId: "FN-4973", kind: "executor", ownerKey: "FN-4973" });
+        throw new ActiveSessionWorktreeRemovalError({
+          worktreePath: CONFLICT_PATH,
+          taskId: "FN-4973",
+          kind: "executor",
+          ownerKey: "FN-4973",
+          reason: worktreePoolModule.RemovalReason.ExecutorDispose,
+        });
+      })
+      .mockResolvedValueOnce(undefined);
+
+    const result = await (executor as any).cleanupConflictingWorktree(CONFLICT_PATH, "fusion/fn-4973", "FN-4973");
+
+    expect(result).toBe(true);
+    expect(removeSpy).toHaveBeenCalledTimes(2);
+    expect(activeSessionRegistry.lookupByPath(CONFLICT_PATH)).toBeNull();
+  });
+});
diff --git a/packages/engine/src/__tests__/reliability-interactions/stale-self-owned-active-session-recovery.test.ts b/packages/engine/src/__tests__/reliability-interactions/stale-self-owned-active-session-recovery.test.ts
new file mode 100644
index 000000000..4d17abaae
--- /dev/null
+++ b/packages/engine/src/__tests__/reliability-interactions/stale-self-owned-active-session-recovery.test.ts
@@ -0,0 +1,136 @@
+import { EventEmitter } from "node:events";
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import "../executor-test-helpers.js";
+import type { Settings, Task, TaskStore } from "@fusion/core";
+import { TaskExecutor } from "../../executor.js";
+import { SelfHealingManager } from "../../self-healing.js";
+import { activeSessionRegistry } from "../../active-session-registry.js";
+import { ActiveSessionWorktreeRemovalError, RemovalReason } from "../../worktree-backend.js";
+import * as worktreePoolModule from "../../worktree-pool.js";
+import { createMockStore, resetExecutorMocks } from "../executor-test-helpers.js";
+
+const TASK_ID = "FN-4973";
+const CONFLICT_PATH = "/tmp/test/.worktrees/solar-flame";
+
+function makeStore(task: Task): TaskStore & EventEmitter {
+  const emitter = new EventEmitter();
+  const settings = {
+    autoMerge: true,
+    globalPause: false,
+    enginePaused: false,
+    baseBranch: "main",
+    mergeStrategy: "direct",
+    autoRecovery: { mode: "deterministic-only", maxRetries: 3 },
+  } as unknown as Settings;
+  return Object.assign(emitter, {
+    getSettings: vi.fn(async () => settings),
+    getTask: vi.fn(async () => task),
+    listTasks: vi.fn(async ({ column }: { column?: string } = {}) => (column === "in-progress" ? [task] : [task])),
+    updateTask: vi.fn(async (_id: string, updates: Partial<Task>) => Object.assign(task, updates)),
+    moveTask: vi.fn(async (_id: string, column: Task["column"]) => {
+      task.column = column;
+      return task;
+    }),
+    logEntry: vi.fn(async () => undefined),
+    appendAgentLog: vi.fn(async () => undefined),
+    updateSettings: vi.fn(async () => settings),
+    clearStaleExecutionStartBranchReferences: vi.fn(() => []),
+    recordRunAuditEvent: vi.fn(async () => undefined),
+    walCheckpoint: vi.fn(() => ({ busy: 0, log: 0, checkpointed: 0 })),
+    archiveTaskAndCleanup: vi.fn(async () => ({})),
+    mergeTask: vi.fn(async () => undefined),
+    getRootDir: vi.fn(() => "/tmp/test"),
+  }) as unknown as TaskStore & EventEmitter;
+}
+
+function makeTask(): Task {
+  return {
+    id: TASK_ID,
+    title: "test",
+    description: "test",
+    column: "in-progress",
+    branch: "fusion/fn-4973",
+    worktree: CONFLICT_PATH,
+    paused: false,
+    userPaused: false,
+    dependencies: [],
+    steps: [],
+    currentStep: 0,
+    log: [],
+    createdAt: new Date().toISOString(),
+    updatedAt: new Date().toISOString(),
+  } as unknown as Task;
+}
+
+describe("FN-4973 reliability interactions: stale self-owned active-session recovery", () => {
+  beforeEach(() => {
+    resetExecutorMocks();
+    activeSessionRegistry.clear();
+    vi.restoreAllMocks();
+  });
+
+  it("FN-4973 reconciles stale self-owned entry and remains clear across self-healing sweeps", async () => {
+    const store = createMockStore();
+    store.listTasks.mockResolvedValue([]);
+    const executor = new TaskExecutor(store, "/tmp/test");
+    activeSessionRegistry.registerPath(CONFLICT_PATH, { taskId: TASK_ID, kind: "executor", ownerKey: TASK_ID });
+
+    vi.spyOn(worktreePoolModule, "removeWorktree").mockResolvedValue(undefined);
+
+    const cleaned = await (executor as any).cleanupConflictingWorktree(CONFLICT_PATH, "fusion/fn-4973", TASK_ID);
+    expect(cleaned).toBe(true);
+    expect(activeSessionRegistry.lookupByPath(CONFLICT_PATH)).toBeNull();
+
+    const task = makeTask();
+    const healingStore = makeStore(task);
+    const manager = new SelfHealingManager(healingStore as any, { rootDir: "/tmp/test" } as any);
+    await manager.reconcileTaskWorktreeMetadata();
+    await manager.reclaimStaleActiveBranches();
+
+    expect(activeSessionRegistry.lookupByPath(CONFLICT_PATH)).toBeNull();
+    manager.stop();
+  });
+
+  it("FN-4973 preserves FN-4811 foreign-task ownership refusal", async () => {
+    const store = createMockStore();
+    store.listTasks.mockResolvedValue([]);
+    const executor = new TaskExecutor(store, "/tmp/test");
+    activeSessionRegistry.registerPath(CONFLICT_PATH, { taskId: "FN-FOREIGN", kind: "executor", ownerKey: "FN-FOREIGN" });
+
+    vi.spyOn(worktreePoolModule, "removeWorktree").mockRejectedValue(
+      new ActiveSessionWorktreeRemovalError({
+        worktreePath: CONFLICT_PATH,
+        taskId: "FN-FOREIGN",
+        kind: "executor",
+        ownerKey: "FN-FOREIGN",
+        reason: RemovalReason.ExecutorDispose,
+      }),
+    );
+
+    const cleaned = await (executor as any).cleanupConflictingWorktree(CONFLICT_PATH, "fusion/fn-4973", TASK_ID);
+    expect(cleaned).toBe(false);
+    expect(activeSessionRegistry.lookupByPath(CONFLICT_PATH)?.taskId).toBe("FN-FOREIGN");
+  });
+
+  it("FN-4973 refuses same-task live in-memory binding", async () => {
+    const store = createMockStore();
+    store.listTasks.mockResolvedValue([]);
+    const executor = new TaskExecutor(store, "/tmp/test");
+    (executor as any).activeWorktrees.set(TASK_ID, CONFLICT_PATH);
+    activeSessionRegistry.registerPath(CONFLICT_PATH, { taskId: TASK_ID, kind: "executor", ownerKey: TASK_ID });
+
+    vi.spyOn(worktreePoolModule, "removeWorktree").mockRejectedValue(
+      new ActiveSessionWorktreeRemovalError({
+        worktreePath: CONFLICT_PATH,
+        taskId: TASK_ID,
+        kind: "executor",
+        ownerKey: TASK_ID,
+        reason: RemovalReason.ExecutorDispose,
+      }),
+    );
+
+    const cleaned = await (executor as any).cleanupConflictingWorktree(CONFLICT_PATH, "fusion/fn-4973", TASK_ID);
+    expect(cleaned).toBe(false);
+    expect(activeSessionRegistry.lookupByPath(CONFLICT_PATH)?.taskId).toBe(TASK_ID);
+  });
+});
diff --git a/packages/engine/src/executor.ts b/packages/engine/src/executor.ts
index e569442a6..9b17c7894 100644
--- a/packages/engine/src/executor.ts
+++ b/packages/engine/src/executor.ts
@@ -43,7 +43,7 @@ import { resolveSandboxBackend } from "./sandbox/index.js";
 import type { SandboxBackend } from "./sandbox/types.js";
 import { ModelRegistry, SessionManager, type ToolDefinition, type AgentSession } from "@mariozechner/pi-coding-agent";
 import { PRIORITY_EXECUTE, type AgentSemaphore } from "./concurrency.js";
-import { RemovalReason, classifyTaskWorktree, describeRegisteredWorktrees, getRegisteredWorktreePaths, isGitRepository, isInsideWorktreesDir, isRegisteredGitWorktree, removeWorktree, type WorktreePool } from "./worktree-pool.js";
+import { ActiveSessionWorktreeRemovalError, RemovalReason, classifyTaskWorktree, describeRegisteredWorktrees, getRegisteredWorktreePaths, isGitRepository, isInsideWorktreesDir, isRegisteredGitWorktree, removeWorktree, type WorktreePool } from "./worktree-pool.js";
 import { activeSessionRegistry, executingTaskLock } from "./active-session-registry.js";
 import {
   StaleWorktreeIndexLockError,
@@ -8865,6 +8865,15 @@ Backward compat fallback: if JSON is unavailable, you may still begin output wit
    * Handles locked worktrees by unlocking first.
    * Returns true if cleanup succeeded.
    */
+  private hasActiveWorktreeBinding(taskId: string, worktreePath: string): boolean {
+    for (const [activeTaskId, activePath] of this.activeWorktrees) {
+      if (activeTaskId === taskId && activePath === worktreePath) {
+        return true;
+      }
+    }
+    return false;
+  }
+
   private async cleanupConflictingWorktree(
     worktreePath: string,
     branch: string,
@@ -8895,15 +8904,47 @@ Backward compat fallback: if JSON is unavailable, you may still begin output wit
         executorLog.warn(`${taskId}: failed to unlock conflicting worktree ${worktreePath} before cleanup: ${msg}`);
       }
 
+      // Remove stale self-owned active-session entry if no live in-memory binding exists.
+      const activeSessionRecord = activeSessionRegistry.lookupByPath(worktreePath);
+      if (activeSessionRecord?.taskId === taskId && !this.hasActiveWorktreeBinding(taskId, worktreePath)) {
+        const reconcileResult = activeSessionRegistry.reconcileStaleSelfOwned(worktreePath, taskId);
+        if (reconcileResult.reconciled) {
+          await this.store.logEntry(taskId, "Reconciled stale self-owned active-session registration", worktreePath);
+          executorLog.log(
+            `[executor] reconciled stale self-owned active-session entry taskId=${taskId} worktreePath=${worktreePath} reason=${reconcileResult.reason}`,
+          );
+        }
+      }
+
       // Remove the worktree
       const settings = await this.store.getSettings();
-      await removeWorktree({
+      const removeArgs = {
         worktreePath,
         rootDir: this.rootDir,
         settings,
         taskId,
         reason: RemovalReason.ExecutorDispose,
-      });
+      } as const;
+      try {
+        await removeWorktree(removeArgs);
+      } catch (error: unknown) {
+        if (
+          error instanceof ActiveSessionWorktreeRemovalError
+          && error.details.taskId === taskId
+          && !this.hasActiveWorktreeBinding(taskId, worktreePath)
+        ) {
+          const reconcileResult = activeSessionRegistry.reconcileStaleSelfOwned(worktreePath, taskId);
+          if (reconcileResult.reconciled) {
+            await this.store.logEntry(taskId, "Reconciled stale self-owned active-session registration", worktreePath);
+            executorLog.log(
+              `[executor] reconciled stale self-owned active-session entry taskId=${taskId} worktreePath=${worktreePath} reason=${reconcileResult.reason}`,
+            );
+          }
+          await removeWorktree(removeArgs);
+        } else {
+          throw error;
+        }
+      }
       await this.store.logEntry(taskId, `Removed conflicting worktree`, worktreePath);
 
       // Delete the branch if it exists