diff --git a/tools/inspector_protocol/lib/Allocator_h.template b/tools/inspector_protocol/lib/Allocator_h.template
index 15eaaaff0236d2..d94c4ca5b0ae99 100644
--- a/tools/inspector_protocol/lib/Allocator_h.template
+++ b/tools/inspector_protocol/lib/Allocator_h.template
@@ -11,8 +11,6 @@
 namespace {{namespace}} {
 {% endfor %}
 
-enum NotNullTagEnum { NotNullLiteral };
-
 #define PROTOCOL_DISALLOW_COPY(ClassName) \
     private: \
         ClassName(const ClassName&) = delete; \