diff --git a/backend/requirements.txt b/backend/requirements.txt
index ad9ffa0..5c154a6 100644
--- a/backend/requirements.txt
+++ b/backend/requirements.txt
@@ -1,6 +1,6 @@
 fastapi==0.115.6
 uvicorn==0.34.0
-anthropic>=0.42.0
+anthropic>=0.120.0
 python-dotenv>=1.0.0
 python-multipart>=0.0.9
 # Browser verification (Task 06.2B/C) drives a headless Chromium via Playwright.