News.com: AT&T sues eBay, PayPal over patent
The suit, filed in federal district court in Delaware, claims that eBay and PayPal’s online payment systems infringe on AT&T patent No. 5,329,589, “Mediation of transactions by a communications system.”
That patent, according to an AT&T release announcing the suit, describes “transactions in which a trusted intermediary securely processes payments over a communications system such as the Internet. The use of a trusted intermediary ensures that one party will not have to disclose sensitive information, such as a credit card number or bank account number, to the other party to the transaction.”