diff --git a/p4_constraints/BUILD.bazel b/p4_constraints/BUILD.bazel
index 7e3a20e..bb22274 100644
--- a/p4_constraints/BUILD.bazel
+++ b/p4_constraints/BUILD.bazel
@@ -1,3 +1,4 @@
+# GOOGLE ONLY (DO NOT REMOVE): load("//third_party/protobuf/bazel:proto_library.bzl", "proto_library")
 load("@rules_cc//cc:defs.bzl", "cc_proto_library")
 load("@rules_proto//proto:defs.bzl", "proto_library")