diff --git a/zipline/pipeline/loaders/base.py b/zipline/pipeline/loaders/base.py
index 5e8b84b7..0f5dcedb 100644
--- a/zipline/pipeline/loaders/base.py
+++ b/zipline/pipeline/loaders/base.py
@@ -17,5 +17,5 @@ class PipelineLoader(with_metaclass(ABCMeta)):
     TODO: DOCUMENT THIS MORE!
     """
     @abstractmethod
-    def load_adjusted_array(self, columns, mask):
+    def load_adjusted_array(self, columns, dates, assets, mask):
         pass