diff --git a/python/ql/test/experimental/query-tests/Security/CWE-1427-PromptInjection/anthropic_test.py b/python/ql/test/experimental/query-tests/Security/CWE-1427-PromptInjection/anthropic_test.py
new file mode 100644
index 00000000000..f9e37e31b3c
--- /dev/null
+++ b/python/ql/test/experimental/query-tests/Security/CWE-1427-PromptInjection/anthropic_test.py
@@ -0,0 +1,63 @@
+from anthropic import Anthropic, AsyncAnthropic
+from flask import Flask, request  # $ Source
+
+app = Flask(__name__)
+client = Anthropic()
+async_client = AsyncAnthropic()
+
+
+@app.route("/anthropic")
+async def get_input_anthropic():
+    persona = request.args.get("persona")
+    query = request.args.get("query")
+
+    response1 = client.messages.create(
+        model="claude-sonnet-4-20250514",
+        max_tokens=256,
+        system="Talk like " + persona,  # $ Alert[py/prompt-injection]
+        messages=[
+            {
+                "role": "user",
+                "content": query,  # $ Alert[py/prompt-injection]
+            }
+        ],
+    )
+
+    response2 = client.messages.stream(
+        model="claude-sonnet-4-20250514",
+        max_tokens=256,
+        system="Talk like " + persona,  # $ Alert[py/prompt-injection]
+        messages=[
+            {
+                "role": "user",
+                "content": query,  # $ Alert[py/prompt-injection]
+            }
+        ],
+    )
+
+    response3 = await async_client.messages.create(
+        model="claude-sonnet-4-20250514",
+        max_tokens=256,
+        system="Talk like " + persona,  # $ Alert[py/prompt-injection]
+        messages=[
+            {
+                "role": "user",
+                "content": query,  # $ Alert[py/prompt-injection]
+            }
+        ],
+    )
+
+    response4 = client.beta.messages.create(
+        model="claude-sonnet-4-20250514",
+        max_tokens=256,
+        system="Talk like " + persona,  # $ Alert[py/prompt-injection]
+        messages=[
+            {
+                "role": "user",
+                "content": query,  # $ Alert[py/prompt-injection]
+            }
+        ],
+        betas=["prompt-caching-2024-07-31"],
+    )
+
+    print(response1, response2, response3, response4)
\ No newline at end of file