diff --git a/Library/Homebrew/tab.rb b/Library/Homebrew/tab.rb
index 379f2e8a42..06ee1693fb 100644
--- a/Library/Homebrew/tab.rb
+++ b/Library/Homebrew/tab.rb
@@ -60,7 +60,6 @@ class Tab < OpenStruct
   def self.from_file_content(content, path)
     attributes = Utils::JSON.load(content)
     attributes["tabfile"] = path
-    attributes["runtime_dependencies"] ||= []
     attributes["source_modified_time"] ||= 0
     attributes["source"] ||= {}
 
diff --git a/Library/Homebrew/test/test_tab.rb b/Library/Homebrew/test/test_tab.rb
index 18d0f49b12..e41f76e274 100644
--- a/Library/Homebrew/test/test_tab.rb
+++ b/Library/Homebrew/test/test_tab.rb
@@ -97,7 +97,7 @@ class TabTests < Homebrew::TestCase
     assert_equal TEST_SHA1, tab.HEAD
     assert_equal :clang, tab.cxxstdlib.compiler
     assert_equal :libcxx, tab.cxxstdlib.type
-    assert_empty tab.runtime_dependencies
+    assert_nil tab.runtime_dependencies
   end
 
   def test_from_file