diff --git a/src/packaging/specifiers.py b/src/packaging/specifiers.py
index 94448327..fc5228d0 100644
--- a/src/packaging/specifiers.py
+++ b/src/packaging/specifiers.py
@@ -82,6 +82,7 @@ def prereleases(self) -> Optional[bool]:
         """
 
     @prereleases.setter
+    @abc.abstractmethod
     def prereleases(self, value: bool) -> None:
         """Setter for :attr:`prereleases`.