diff --git a/Gemfile.lock b/Gemfile.lock
index 1eac6a9..f40afa8 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -16,7 +16,7 @@ GEM
     rspec-expectations (2.6.0)
       diff-lcs (~> 1.1.2)
     rspec-mocks (2.6.0)
-    yard (0.7.2)
+    yard (0.9.20)
 
 PLATFORMS
   ruby