diff --git a/frontend/src/stores/__tests__/announcements.fetch.spec.ts b/frontend/src/stores/__tests__/announcements.fetch.spec.ts
new file mode 100644
index 0000000000..6edfa22fbc
--- /dev/null
+++ b/frontend/src/stores/__tests__/announcements.fetch.spec.ts
@@ -0,0 +1,106 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
+import { createPinia, setActivePinia } from 'pinia'
+import { useAnnouncementStore } from '../announcements'
+import type { UserAnnouncement } from '@/types'
+
+const list = vi.hoisted(() => vi.fn())
+vi.mock('@/api', () => ({ announcementsAPI: { list } }))
+
+const notice = (id: number): UserAnnouncement => ({
+  id, title: `Notice ${id}`, content: 'Content', notify_mode: 'popup',
+  created_at: '2026-09-18T00:00:00Z', updated_at: '2026-09-18T00:00:00Z'
+})
+
+function pendingList() {
+  let resolve!: (value: UserAnnouncement[]) => void
+  let reject!: (reason: Error) => void
+  const promise = new Promise<UserAnnouncement[]>((res, rej) => { resolve = res; reject = rej })
+  return { promise, resolve, reject }
+}
+
+beforeEach(() => {
+  setActivePinia(createPinia())
+  vi.resetAllMocks()
+  vi.spyOn(console, 'error').mockImplementation(() => {})
+})
+afterEach(() => vi.restoreAllMocks())
+
+describe('announcement fetch ownership', () => {
+  it('does not restore announcements or popups after logout resets the store', async () => {
+    const store = useAnnouncementStore()
+    const old = pendingList()
+    list.mockReturnValueOnce(old.promise)
+    const request = store.fetchAnnouncements()
+    store.reset()
+    old.resolve([notice(1)])
+    await request
+    expect(store.announcements).toEqual([])
+    expect(store.currentPopup).toBeNull()
+    expect(store.loading).toBe(false)
+  })
+
+  it('keeps the new session loading when an old request finishes', async () => {
+    const store = useAnnouncementStore()
+    const old = pendingList()
+    const current = pendingList()
+    list.mockReturnValueOnce(old.promise).mockReturnValueOnce(current.promise)
+    const oldRequest = store.fetchAnnouncements()
+    store.reset()
+    const currentRequest = store.fetchAnnouncements()
+    old.resolve([])
+    await oldRequest
+    expect(store.loading).toBe(true)
+    current.resolve([notice(2)])
+    await currentRequest
+    expect(store.announcements.map(a => a.id)).toEqual([2])
+    expect(store.loading).toBe(false)
+  })
+
+  it('keeps the latest forced refresh when responses arrive out of order', async () => {
+    const store = useAnnouncementStore()
+    const old = pendingList()
+    list.mockReturnValueOnce(old.promise).mockResolvedValueOnce([notice(2)])
+    const oldRequest = store.fetchAnnouncements()
+    await store.fetchAnnouncements(true)
+    old.resolve([notice(1)])
+    await oldRequest
+    expect(store.announcements.map(a => a.id)).toEqual([2])
+    expect(store.currentPopup?.id).toBe(2)
+  })
+
+  it('does not clear the new session throttle when an old request rejects', async () => {
+    const store = useAnnouncementStore()
+    const old = pendingList()
+    list.mockReturnValueOnce(old.promise).mockResolvedValue([notice(2)])
+    const oldRequest = store.fetchAnnouncements()
+    store.reset()
+    await store.fetchAnnouncements()
+    old.reject(new Error('old request failed'))
+    await oldRequest
+    await store.fetchAnnouncements()
+    expect(list).toHaveBeenCalledTimes(2)
+    expect(store.announcements.map(a => a.id)).toEqual([2])
+  })
+
+  it('still retries a failed current request', async () => {
+    const store = useAnnouncementStore()
+    list.mockRejectedValueOnce(new Error('offline')).mockResolvedValueOnce([notice(1)])
+    await store.fetchAnnouncements()
+    await store.fetchAnnouncements()
+    expect(list).toHaveBeenCalledTimes(2)
+    expect(store.currentPopup?.id).toBe(1)
+  })
+
+  it('still throttles ordinary concurrent fetches', async () => {
+    const store = useAnnouncementStore()
+    const current = pendingList()
+    list.mockReturnValueOnce(current.promise)
+    const request = store.fetchAnnouncements()
+    await store.fetchAnnouncements()
+    expect(list).toHaveBeenCalledTimes(1)
+    expect(store.loading).toBe(true)
+    current.resolve([])
+    await request
+    expect(store.loading).toBe(false)
+  })
+})
diff --git a/frontend/src/stores/announcements.ts b/frontend/src/stores/announcements.ts
index 90c6ad2385..e8dac58ad5 100644
--- a/frontend/src/stores/announcements.ts
+++ b/frontend/src/stores/announcements.ts
@@ -15,6 +15,7 @@ export const useAnnouncementStore = defineStore('announcements', () => {
 
   // Session-scoped dedup set — not reactive, used as plain lookup only
   let shownPopupIds = new Set<number>()
+  let fetchGeneration = 0
 
   // Getters
   const unreadCount = computed(() =>
@@ -30,18 +31,21 @@ export const useAnnouncementStore = defineStore('announcements', () => {
 
     // Set immediately to prevent concurrent duplicate requests
     lastFetchTime.value = now
+    const generation = ++fetchGeneration
 
     try {
       loading.value = true
       const all = await announcementsAPI.list(false)
+      if (generation !== fetchGeneration) return
       announcements.value = all.slice(0, 20)
       enqueueNewPopups()
     } catch (err: any) {
+      if (generation !== fetchGeneration) return
       // Revert throttle timestamp on failure so retry is allowed
       lastFetchTime.value = 0
       console.error('Failed to fetch announcements:', err)
     } finally {
-      loading.value = false
+      if (generation === fetchGeneration) loading.value = false
     }
   }
 
@@ -118,6 +122,7 @@ export const useAnnouncementStore = defineStore('announcements', () => {
   }
 
   function reset() {
+    fetchGeneration++
     announcements.value = []
     lastFetchTime.value = 0
     shownPopupIds = new Set()