diff --git a/Library/Homebrew/Gemfile.lock b/Library/Homebrew/Gemfile.lock
index f97756760a..720e10855d 100644
--- a/Library/Homebrew/Gemfile.lock
+++ b/Library/Homebrew/Gemfile.lock
@@ -112,7 +112,7 @@ GEM
       rspec (>= 3, < 4)
     rspec_junit_formatter (0.4.1)
       rspec-core (>= 2, < 4, != 2.12.0)
-    rubocop (1.19.1)
+    rubocop (1.20.0)
       parallel (~> 1.10)
       parser (>= 3.0.0.0)
       rainbow (>= 2.2.2, < 4.0)