Some SSNs used in advertising have rendered those numbers invalid. One famous instance of this occurred in 1938 when the E. H. Ferree Company in Lockport, New York, decided to promote its product by showing how a Social Security card would fit into its wallets. A sample card, used for display purposes, was placed in each wallet, which was sold by Woolworth and other department stores across the country; the wallet manufacturer's vice president and treasurer Douglas Patterson used the actual SSN of his secretary, Hilda Schrader Whitcher.