diff --git a/setup.py b/setup.py
index 35308fce9..d2346731c 100644
--- a/setup.py
+++ b/setup.py
@@ -741,6 +741,8 @@ setup(
         "Programming Language :: Python :: 3.2",
         "Programming Language :: Python :: 3.3",
         "Programming Language :: Python :: 3.4",
+        'Programming Language :: Python :: Implementation :: CPython',
+        'Programming Language :: Python :: Implementation :: PyPy',
         ],
     cmdclass={"build_ext": pil_build_ext},
     ext_modules=[Extension("PIL._imaging", ["_imaging.c"])],