diff --git a/activemodel/CHANGELOG.md b/activemodel/CHANGELOG.md
index 789cff0673..eb34edb91b 100644
--- a/activemodel/CHANGELOG.md
+++ b/activemodel/CHANGELOG.md
@@ -1,5 +1,7 @@
 ## Rails 4.0.0 (unreleased) ##
 
+*   Passing false hash values to `validates` will no longer enable the corresponding validators *Steve Purcell*
+
 *   `ConfirmationValidator` error messages will attach to `:#{attribute}_confirmation` instead of `attribute` *Brian Cardarella*
 
 *   Added ActiveModel::Model, a mixin to make Ruby objects work with AP out of box *Guillermo Iguaran*
diff --git a/activemodel/lib/active_model/validations/validates.rb b/activemodel/lib/active_model/validations/validates.rb
index d94c4e3f4f..6c13d2b4a2 100644
--- a/activemodel/lib/active_model/validations/validates.rb
+++ b/activemodel/lib/active_model/validations/validates.rb
@@ -88,6 +88,7 @@ module ActiveModel
         defaults.merge!(:attributes => attributes)
 
         validations.each do |key, options|
+          next unless options
           key = "#{key.to_s.camelize}Validator"
 
           begin
diff --git a/activemodel/test/cases/validations_test.rb b/activemodel/test/cases/validations_test.rb
index 1f5023bf76..8ea9745fbf 100644
--- a/activemodel/test/cases/validations_test.rb
+++ b/activemodel/test/cases/validations_test.rb
@@ -330,6 +330,11 @@ class ValidationsTest < ActiveModel::TestCase
     end
   end
 
+  def test_validates_with_false_hash_value
+    Topic.validates :title,  :presence => false
+    assert Topic.new.valid?
+  end
+
   def test_strict_validation_error_message
     Topic.validates :title, :strict => true, :presence => true