I googled and found this, I guess others had problems removing the ring.
Due to regulations, your free quart of Glidden™ paint is secured by a special locking ring. Here are instructions for removal of the ring.
Place a pair of pliers over the outer portion of the locking ring and clamp down. Apply an upward pressure on the pliers until the locking ring separates from the container. Peel the remaining portion of the locking ring off by hand.
Removing the ring from the container typically causes the locking ring to deform. Therefore, the locking ring is non-reusable after its initial removal.
Still have questions? Feel free to call our customer service line at 1-800-GLIDDEN. Don't forget to allow 3-4 weeks for delivery of your free quart of paint.
Thanks again for your interest in Glidden paint!
The Glidden Team
www.glidden.com