diff --git a/value/src/main/java/com/google/auto/value/extension/serializable/g3doc/index.md b/value/src/main/java/com/google/auto/value/extension/serializable/g3doc/index.md
index 0282404b42..c74c4ac6d5 100644
--- a/value/src/main/java/com/google/auto/value/extension/serializable/g3doc/index.md
+++ b/value/src/main/java/com/google/auto/value/extension/serializable/g3doc/index.md
@@ -98,4 +98,4 @@ un-serializable types with [SerializerExtensions].
 [`AutoValue`]: https://github.com/google/auto/tree/master/value
 [`SerializableAutoValue`]: https://github.com/google/auto/blob/master/value/src/main/java/com/google/auto/value/extension/serializable/SerializableAutoValue.java
 [`SerializableAutoValueExtension`]: https://github.com/google/auto/blob/master/value/src/main/java/com/google/auto/value/extension/serializable/extension/SerializableAutoValueExtension.java
-[SerializerExtensions]: https://github.com/google/auto/blob/master/value/src/main/java/com/google/auto/value/extension/serializable/userguide/serializer-extension.md
+[SerializerExtensions]: serializer-extension