diff --git a/selling/utils/__init__.py b/selling/utils/__init__.py
index fd9c492..5974da7 100644
--- a/selling/utils/__init__.py
+++ b/selling/utils/__init__.py
@@ -1,4 +1,4 @@
-# Copyright (c) 2013, Web Notes Technologies Pvt. Ltd.
+# Copyright (c) 2013, Web Notes Technologies Pvt. Ltd. and Contributors
 # License: GNU General Public License v3. See license.txt
 
 from __future__ import unicode_literals
diff --git a/selling/utils/cart.py b/selling/utils/cart.py
index e48059d..c4c0b72 100644
--- a/selling/utils/cart.py
+++ b/selling/utils/cart.py
@@ -1,4 +1,4 @@
-# Copyright (c) 2013, Web Notes Technologies Pvt. Ltd.
+# Copyright (c) 2013, Web Notes Technologies Pvt. Ltd. and Contributors
 # License: GNU General Public License v3. See license.txt
 
 from __future__ import unicode_literals
diff --git a/selling/utils/product.py b/selling/utils/product.py
index df5f16d..d218979 100644
--- a/selling/utils/product.py
+++ b/selling/utils/product.py
@@ -1,4 +1,4 @@
-# Copyright (c) 2013, Web Notes Technologies Pvt. Ltd.
+# Copyright (c) 2013, Web Notes Technologies Pvt. Ltd. and Contributors
 # License: GNU General Public License v3. See license.txt
 
 from __future__ import unicode_literals