diff --git a/metropolis/node/core/abloader/spec/BUILD.bazel b/metropolis/node/core/abloader/spec/BUILD.bazel
index c53b997..0506d4c 100644
--- a/metropolis/node/core/abloader/spec/BUILD.bazel
+++ b/metropolis/node/core/abloader/spec/BUILD.bazel
@@ -8,7 +8,7 @@
     name = "abloader_proto_lint_test",
     except_rules = [
         "PACKAGE_VERSION_SUFFIX",
-        "ENUM_ZERO_VALUE_SUFFIX",  # TODO: evaluate correctness
+        "ENUM_ZERO_VALUE_SUFFIX",
     ],
     protos = [":abloader_proto"],
     use_rules = [
diff --git a/metropolis/proto/api/BUILD.bazel b/metropolis/proto/api/BUILD.bazel
index bb39de8..e95bb19 100644
--- a/metropolis/proto/api/BUILD.bazel
+++ b/metropolis/proto/api/BUILD.bazel
@@ -7,8 +7,8 @@
     name = "api_proto_lint_test",
     except_rules = [
         "PACKAGE_VERSION_SUFFIX",
+        "ENUM_ZERO_VALUE_SUFFIX",
         "RPC_REQUEST_RESPONSE_UNIQUE",  # TODO: evaluate correctness
-        "ENUM_ZERO_VALUE_SUFFIX",  # TODO: evaluate correctness
         "RPC_REQUEST_STANDARD_NAME",  # TODO: evaluate correctness
         "RPC_RESPONSE_STANDARD_NAME",  # TODO: evaluate correctness
         "SERVICE_SUFFIX",  # TODO: evaluate correctness
diff --git a/metropolis/proto/common/BUILD.bazel b/metropolis/proto/common/BUILD.bazel
index f0219fe..8c9b529 100644
--- a/metropolis/proto/common/BUILD.bazel
+++ b/metropolis/proto/common/BUILD.bazel
@@ -7,7 +7,7 @@
     name = "common_proto_lint_test",
     except_rules = [
         "PACKAGE_VERSION_SUFFIX",
-        "ENUM_ZERO_VALUE_SUFFIX",  # TODO: evaluate correctness
+        "ENUM_ZERO_VALUE_SUFFIX",
     ],
     protos = [":common_proto"],
     use_rules = [