diff --git a/Library/Homebrew/rubocops/lines.rb b/Library/Homebrew/rubocops/lines.rb
index 26e36f1397..0f2721670d 100644
--- a/Library/Homebrew/rubocops/lines.rb
+++ b/Library/Homebrew/rubocops/lines.rb
@@ -439,6 +439,7 @@ module RuboCop
               open-mpi
               openssl@1.1
               pcre
+              protobuf
               wolfssl
               xz
             ].include?(@formula_name)