diff --git a/Gemfile.lock b/Gemfile.lock
index 9590c74..769fb89 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -16,7 +16,7 @@ GEM
     rspec-expectations (2.10.0)
       diff-lcs (~> 1.1.3)
     rspec-mocks (2.10.1)
-    yard (0.8.1)
+    yard (0.9.20)
 
 PLATFORMS
   ruby