diff --git a/src/lib/api/middleware/auth.js b/src/lib/api/middleware/auth.js
index 2bcc51ea..f07821ef 100644
--- a/src/lib/api/middleware/auth.js
+++ b/src/lib/api/middleware/auth.js
@@ -1,11 +1,20 @@
 import { createSupabaseServerClient, createSupabaseServerClientWithToken } from '@/lib/supabase.js';
 import { NextResponse } from 'next/server';
 
+export function getBearerToken(authHeader) {
+  if (typeof authHeader !== 'string') return null;
+
+  const match = authHeader.match(/^Bearer\s+(.+)$/i);
+  const token = match?.[1]?.trim();
+
+  return token || null;
+}
+
 export async function authenticateRequest(request) {
   try {
     // Check Authorization header first (Bearer token), then fall back to cookies
     const authHeader = request.headers.get('authorization');
-    const token = authHeader?.startsWith('Bearer ') ? authHeader.slice(7) : null;
+    const token = getBearerToken(authHeader);
 
     const supabase = token
       ? await createSupabaseServerClientWithToken(token)
diff --git a/src/lib/api/middleware/auth.test.js b/src/lib/api/middleware/auth.test.js
new file mode 100644
index 00000000..32cd2403
--- /dev/null
+++ b/src/lib/api/middleware/auth.test.js
@@ -0,0 +1,67 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+
+const mocks = vi.hoisted(() => ({
+  cookieClient: {
+    auth: {
+      getUser: vi.fn()
+    }
+  },
+  tokenClient: {
+    auth: {
+      getUser: vi.fn()
+    }
+  },
+  createSupabaseServerClient: vi.fn(),
+  createSupabaseServerClientWithToken: vi.fn()
+}));
+
+vi.mock('@/lib/supabase.js', () => ({
+  createSupabaseServerClient: mocks.createSupabaseServerClient,
+  createSupabaseServerClientWithToken: mocks.createSupabaseServerClientWithToken
+}));
+
+function requestWithAuthorization(value) {
+  return {
+    headers: {
+      get: (name) => (name === 'authorization' ? value : null)
+    }
+  };
+}
+
+describe('authenticateRequest bearer token parsing', () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    mocks.cookieClient.auth.getUser.mockResolvedValue({
+      data: { user: null },
+      error: { message: 'missing cookie session' }
+    });
+    mocks.tokenClient.auth.getUser.mockResolvedValue({
+      data: { user: { id: 'user-1' } },
+      error: null
+    });
+    mocks.createSupabaseServerClient.mockResolvedValue(mocks.cookieClient);
+    mocks.createSupabaseServerClientWithToken.mockResolvedValue(mocks.tokenClient);
+  });
+
+  it('accepts bearer tokens with case-insensitive schemes and extra spaces', async () => {
+    const { authenticateRequest } = await import('./auth.js');
+
+    const auth = await authenticateRequest(requestWithAuthorization('bearer   access-token-123  '));
+
+    expect(auth.success).toBe(true);
+    expect(auth.user).toEqual({ id: 'user-1' });
+    expect(mocks.createSupabaseServerClientWithToken).toHaveBeenCalledWith('access-token-123');
+    expect(mocks.createSupabaseServerClient).not.toHaveBeenCalled();
+  });
+
+  it('falls back to cookies when the authorization header has no token', async () => {
+    const { authenticateRequest } = await import('./auth.js');
+
+    const auth = await authenticateRequest(requestWithAuthorization('Bearer   '));
+
+    expect(auth.success).toBe(false);
+    expect(auth.error).toBe('Unauthorized');
+    expect(mocks.createSupabaseServerClientWithToken).not.toHaveBeenCalled();
+    expect(mocks.createSupabaseServerClient).toHaveBeenCalledTimes(1);
+  });
+});