diff --git a/docs_src/app_testing/app_b_an/main.py b/docs_src/app_testing/app_b_an/main.py
index c63134fc9..c66278fdd 100644
--- a/docs_src/app_testing/app_b_an/main.py
+++ b/docs_src/app_testing/app_b_an/main.py
@@ -34,6 +34,6 @@ async def create_item(item: Item, x_token: Annotated[str, Header()]):
     if x_token != fake_secret_token:
         raise HTTPException(status_code=400, detail="Invalid X-Token header")
     if item.id in fake_db:
-        raise HTTPException(status_code=400, detail="Item already exists")
+        raise HTTPException(status_code=409, detail="Item already exists")
     fake_db[item.id] = item
     return item
diff --git a/docs_src/app_testing/app_b_an/test_main.py b/docs_src/app_testing/app_b_an/test_main.py
index e2eda449d..4e1c51ecc 100644
--- a/docs_src/app_testing/app_b_an/test_main.py
+++ b/docs_src/app_testing/app_b_an/test_main.py
@@ -61,5 +61,5 @@ def test_create_existing_item():
             "description": "There goes my stealer",
         },
     )
-    assert response.status_code == 400
+    assert response.status_code == 409
     assert response.json() == {"detail": "Item already exists"}
diff --git a/docs_src/app_testing/app_b_an_py310/main.py b/docs_src/app_testing/app_b_an_py310/main.py
index 48c27a0b8..c5952be0b 100644
--- a/docs_src/app_testing/app_b_an_py310/main.py
+++ b/docs_src/app_testing/app_b_an_py310/main.py
@@ -33,6 +33,6 @@ async def create_item(item: Item, x_token: Annotated[str, Header()]):
     if x_token != fake_secret_token:
         raise HTTPException(status_code=400, detail="Invalid X-Token header")
     if item.id in fake_db:
-        raise HTTPException(status_code=400, detail="Item already exists")
+        raise HTTPException(status_code=409, detail="Item already exists")
     fake_db[item.id] = item
     return item
diff --git a/docs_src/app_testing/app_b_an_py310/test_main.py b/docs_src/app_testing/app_b_an_py310/test_main.py
index e2eda449d..4e1c51ecc 100644
--- a/docs_src/app_testing/app_b_an_py310/test_main.py
+++ b/docs_src/app_testing/app_b_an_py310/test_main.py
@@ -61,5 +61,5 @@ def test_create_existing_item():
             "description": "There goes my stealer",
         },
     )
-    assert response.status_code == 400
+    assert response.status_code == 409
     assert response.json() == {"detail": "Item already exists"}
diff --git a/docs_src/app_testing/app_b_an_py39/main.py b/docs_src/app_testing/app_b_an_py39/main.py
index 935a510b7..142e23a26 100644
--- a/docs_src/app_testing/app_b_an_py39/main.py
+++ b/docs_src/app_testing/app_b_an_py39/main.py
@@ -33,6 +33,6 @@ async def create_item(item: Item, x_token: Annotated[str, Header()]):
     if x_token != fake_secret_token:
         raise HTTPException(status_code=400, detail="Invalid X-Token header")
     if item.id in fake_db:
-        raise HTTPException(status_code=400, detail="Item already exists")
+        raise HTTPException(status_code=409, detail="Item already exists")
     fake_db[item.id] = item
     return item
diff --git a/docs_src/app_testing/app_b_an_py39/test_main.py b/docs_src/app_testing/app_b_an_py39/test_main.py
index e2eda449d..4e1c51ecc 100644
--- a/docs_src/app_testing/app_b_an_py39/test_main.py
+++ b/docs_src/app_testing/app_b_an_py39/test_main.py
@@ -61,5 +61,5 @@ def test_create_existing_item():
             "description": "There goes my stealer",
         },
     )
-    assert response.status_code == 400
+    assert response.status_code == 409
     assert response.json() == {"detail": "Item already exists"}