diff --git a/__tests__/actions/story-claim.test.ts b/__tests__/actions/story-claim.test.ts
new file mode 100644
index 0000000..94b6e57
--- /dev/null
+++ b/__tests__/actions/story-claim.test.ts
@@ -0,0 +1,158 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+
+vi.mock('next/cache', () => ({ revalidatePath: vi.fn() }))
+vi.mock('next/headers', () => ({ cookies: vi.fn().mockResolvedValue({}) }))
+vi.mock('iron-session', () => ({
+  getIronSession: vi.fn().mockResolvedValue({ userId: 'user-1', isDemo: false }),
+}))
+vi.mock('@/lib/session', () => ({
+  sessionOptions: { cookieName: 'test', password: 'test' },
+}))
+vi.mock('@/lib/auth', () => ({
+  requireProductWriter: vi.fn().mockResolvedValue({ id: 'product-1', user_id: 'user-1' }),
+}))
+vi.mock('@/lib/prisma', () => ({
+  prisma: {
+    story: {
+      findFirst: vi.fn(),
+      update: vi.fn(),
+      updateMany: vi.fn(),
+    },
+    product: {
+      findFirst: vi.fn(),
+    },
+    sprint: {
+      findFirst: vi.fn(),
+    },
+  },
+}))
+
+import { prisma } from '@/lib/prisma'
+import { requireProductWriter } from '@/lib/auth'
+import { getIronSession } from 'iron-session'
+import {
+  claimStoryAction,
+  unclaimStoryAction,
+  reassignStoryAction,
+  claimAllUnassignedInActiveSprintAction,
+} from '@/actions/stories'
+
+const mockPrisma = prisma as {
+  story: {
+    findFirst: ReturnType<typeof vi.fn>
+    update: ReturnType<typeof vi.fn>
+    updateMany: ReturnType<typeof vi.fn>
+  }
+  product: { findFirst: ReturnType<typeof vi.fn> }
+  sprint: { findFirst: ReturnType<typeof vi.fn> }
+}
+const mockRequireProductWriter = requireProductWriter as ReturnType<typeof vi.fn>
+const mockGetIronSession = getIronSession as ReturnType<typeof vi.fn>
+
+const STORY = { id: 'story-1', product_id: 'product-1', assignee_id: null }
+const SPRINT = { id: 'sprint-1', product_id: 'product-1', status: 'ACTIVE' }
+
+beforeEach(() => {
+  vi.clearAllMocks()
+  mockRequireProductWriter.mockResolvedValue({ id: 'product-1', user_id: 'user-1' })
+  mockGetIronSession.mockResolvedValue({ userId: 'user-1', isDemo: false })
+  mockPrisma.story.findFirst.mockResolvedValue(STORY)
+  mockPrisma.story.update.mockResolvedValue({ ...STORY, assignee_id: 'user-1' })
+  mockPrisma.story.updateMany.mockResolvedValue({ count: 2 })
+  mockPrisma.product.findFirst.mockResolvedValue({ id: 'product-1' })
+  mockPrisma.sprint.findFirst.mockResolvedValue(SPRINT)
+})
+
+describe('claimStoryAction', () => {
+  it('sets assignee_id to current user', async () => {
+    const result = await claimStoryAction('story-1', 'product-1')
+    expect(result).toEqual({ success: true })
+    expect(mockPrisma.story.update).toHaveBeenCalledWith({
+      where: { id: 'story-1' },
+      data: { assignee_id: 'user-1' },
+    })
+  })
+
+  it('returns error when demo user tries to claim', async () => {
+    mockRequireProductWriter.mockRejectedValue(new Error('Niet beschikbaar in demo-modus'))
+    const result = await claimStoryAction('story-1', 'product-1')
+    expect(result).toEqual({ error: 'Niet beschikbaar in demo-modus' })
+    expect(mockPrisma.story.update).not.toHaveBeenCalled()
+  })
+
+  it('returns error when story not found', async () => {
+    mockPrisma.story.findFirst.mockResolvedValue(null)
+    const result = await claimStoryAction('story-1', 'product-1')
+    expect(result).toEqual({ error: 'Story niet gevonden' })
+  })
+})
+
+describe('unclaimStoryAction', () => {
+  it('sets assignee_id to null', async () => {
+    const result = await unclaimStoryAction('story-1', 'product-1')
+    expect(result).toEqual({ success: true })
+    expect(mockPrisma.story.update).toHaveBeenCalledWith({
+      where: { id: 'story-1' },
+      data: { assignee_id: null },
+    })
+  })
+
+  it('returns error when demo user tries to unclaim', async () => {
+    mockRequireProductWriter.mockRejectedValue(new Error('Niet beschikbaar in demo-modus'))
+    const result = await unclaimStoryAction('story-1', 'product-1')
+    expect(result).toEqual({ error: 'Niet beschikbaar in demo-modus' })
+  })
+})
+
+describe('reassignStoryAction', () => {
+  it('reassigns story to a valid member', async () => {
+    const result = await reassignStoryAction('story-1', 'product-1', 'user-2')
+    expect(result).toEqual({ success: true })
+    expect(mockPrisma.story.update).toHaveBeenCalledWith({
+      where: { id: 'story-1' },
+      data: { assignee_id: 'user-2' },
+    })
+  })
+
+  it('returns error when target user is not a product member', async () => {
+    mockPrisma.product.findFirst.mockResolvedValue(null)
+    const result = await reassignStoryAction('story-1', 'product-1', 'outsider')
+    expect(result).toEqual({ error: 'Gebruiker is geen lid van dit product' })
+    expect(mockPrisma.story.update).not.toHaveBeenCalled()
+  })
+
+  it('returns error when demo user tries to reassign', async () => {
+    mockRequireProductWriter.mockRejectedValue(new Error('Niet beschikbaar in demo-modus'))
+    const result = await reassignStoryAction('story-1', 'product-1', 'user-2')
+    expect(result).toEqual({ error: 'Niet beschikbaar in demo-modus' })
+  })
+})
+
+describe('claimAllUnassignedInActiveSprintAction', () => {
+  it('claims all unassigned stories in active sprint', async () => {
+    const result = await claimAllUnassignedInActiveSprintAction('product-1')
+    expect(result).toEqual({ success: true, count: 2 })
+    expect(mockPrisma.story.updateMany).toHaveBeenCalledWith({
+      where: { sprint_id: 'sprint-1', product_id: 'product-1', assignee_id: null },
+      data: { assignee_id: 'user-1' },
+    })
+  })
+
+  it('only claims stories with assignee_id null', async () => {
+    await claimAllUnassignedInActiveSprintAction('product-1')
+    const call = mockPrisma.story.updateMany.mock.calls[0][0]
+    expect(call.where.assignee_id).toBeNull()
+  })
+
+  it('returns error when no active sprint exists', async () => {
+    mockPrisma.sprint.findFirst.mockResolvedValue(null)
+    const result = await claimAllUnassignedInActiveSprintAction('product-1')
+    expect(result).toEqual({ error: 'Geen actieve sprint gevonden' })
+  })
+
+  it('returns error when demo user tries to claim all', async () => {
+    mockRequireProductWriter.mockRejectedValue(new Error('Niet beschikbaar in demo-modus'))
+    const result = await claimAllUnassignedInActiveSprintAction('product-1')
+    expect(result).toEqual({ error: 'Niet beschikbaar in demo-modus' })
+  })
+})