I am at Barnes & Noble in Columbia Missouri drinking a Starbucks Brand latte. My cup is insulated with a removable corrugated cardboard insulator that is marked with U.S. Patent. No. 5,205,473. By my calculation, that patent expires April 27, 2010. (17 years from the April 27, 1993 issue date.) It will be interesting to see how long it takes for the company to remove the patent number once expired (in 2012..).
The ‘473 patent is assigned to LBP Manufacturing of Chicago, but Starbucks could still be liable if it improperly marking its products.