diff --git a/app/models/oauth2_provider_models_activerecord_authorization.rb b/app/models/oauth2_provider_models_activerecord_authorization.rb
index 1bbb9b758..b8f0f1d24 100644
--- a/app/models/oauth2_provider_models_activerecord_authorization.rb
+++ b/app/models/oauth2_provider_models_activerecord_authorization.rb
@@ -1,4 +1,4 @@
 class OAuth2::Provider::Models::ActiveRecord::Authorization
   validates_presence_of :resource_owner_id, :resource_owner_type
-  validates_uniqueness_of [:resource_owner_id, :resource_owner_type] , :scope => :client_id
+  validates_uniqueness_of :resource_owner_id, :scope => [:client_id, :resource_owner_type]
 end