diff --git a/value/src/main/java/com/google/auto/value/processor/AutoAnnotationProcessor.java b/value/src/main/java/com/google/auto/value/processor/AutoAnnotationProcessor.java
index 02a519b131..ba7f806cdc 100644
--- a/value/src/main/java/com/google/auto/value/processor/AutoAnnotationProcessor.java
+++ b/value/src/main/java/com/google/auto/value/processor/AutoAnnotationProcessor.java
@@ -182,7 +182,7 @@ private void processMethod(ExecutableElement method) {
   private String getGeneratedTypeName() {
     return generatedAnnotation(elementUtils, processingEnv.getSourceVersion())
         .map(generatedAnnotation -> TypeEncoder.encode(generatedAnnotation.asType()))
-        .orElse(null);
+        .orElse("");
   }
 
   /**