diff --git a/stubs/Reflection.phpstub b/stubs/Reflection.phpstub
index 6c86eaa13ec..96297790dd7 100644
--- a/stubs/Reflection.phpstub
+++ b/stubs/Reflection.phpstub
@@ -215,7 +215,7 @@ class ReflectionClass implements Reflector {
     public function newInstanceWithoutConstructor(): object {}
 
     /** @psalm-pure */
-    public function getParentClass(): ?ReflectionClass {}
+    public function getParentClass(): ReflectionClass|false {}
 
     /**
      * @param ReflectionClass|class-string $class