diff --git a/Text/Pandoc/Shared.hs b/Text/Pandoc/Shared.hs
index ea576472d..a310daaf0 100644
--- a/Text/Pandoc/Shared.hs
+++ b/Text/Pandoc/Shared.hs
@@ -1,3 +1,4 @@
+{-# OPTIONS_GHC -fno-warn-orphans #-}
 {-
 Copyright (C) 2006-8 John MacFarlane <jgm@berkeley.edu>