diff --git a/tools/test/build_api/build_api_test.py b/tools/test/build_api/build_api_test.py
index a76cde5b15..34a157e2bf 100755
--- a/tools/test/build_api/build_api_test.py
+++ b/tools/test/build_api/build_api_test.py
@@ -66,7 +66,6 @@ class BuildApiTests(unittest.TestCase):
     @patch('tools.toolchains.mbedToolchain.need_update',
            side_effect=[i % 2 for i in range(3000)])
     @patch('os.mkdir')
-    @patch('tools.toolchains.exists', return_value=True)
     @patch('tools.toolchains.mbedToolchain.dump_build_profile')
     @patch('tools.utils.run_cmd', return_value=(b'', b'', 0))
     def test_always_complete_build(self, *_):