diff --git a/src/python/pants/util/meta.py b/src/python/pants/util/meta.py
index 9d66d63af156..875a487763a9 100644
--- a/src/python/pants/util/meta.py
+++ b/src/python/pants/util/meta.py
@@ -190,4 +190,4 @@ def new_setattr(self, key: str, value: Any) -> None:
   cls.__init__ = new_init  # type: ignore[assignment]
   cls.__setattr__ = new_setattr  # type: ignore[assignment]
 
-  return frozen_after_init.define_instance_of(cls)
+  return cls
diff --git a/tests/python/pants_test/util/test_meta.py b/tests/python/pants_test/util/test_meta.py
index 2ddf62306d76..dd7ec88a3936 100644
--- a/tests/python/pants_test/util/test_meta.py
+++ b/tests/python/pants_test/util/test_meta.py
@@ -266,6 +266,19 @@ class C:
     self.assertEqual(C._decorated_type_checkable_type, type(f))
     self.assertTrue(f.is_instance(C))
 
+    # Check that .is_instance() is only true for exactly the decorator @g used on the class D!
+    @decorated_type_checkable
+    def g(cls):
+      return g.define_instance_of(cls)
+
+    @g
+    class D:
+      pass
+
+    self.assertEqual(D._decorated_type_checkable_type, type(g))
+    self.assertTrue(g.is_instance(D))
+    self.assertFalse(f.is_instance(D))
+
 
 class FrozenAfterInitTest(unittest.TestCase):