diff --git a/modules/rubiconBidAdapter.js b/modules/rubiconBidAdapter.js
index c3d0b48f14b..881ce480aef 100644
--- a/modules/rubiconBidAdapter.js
+++ b/modules/rubiconBidAdapter.js
@@ -83,6 +83,7 @@ var sizeMap = {
   126: '200x600',
   144: '980x600',
   145: '980x150',
+  156: '640x320',
   159: '320x250',
   179: '250x600',
   195: '600x300',