Ottawa-based Wi-LAN, which patents wireless products, is suing around 18 of the tech industry's largest players over what it claims are patent violations of Bluetooth technology. More specifically, Wi-LAN is alleging that these companies--which include Acer, Apple, Dell, Hewlett-Packard, Lenovo, Motorola, Sony, and Toshiba--have all infringed on one of its U.S. patents for selling PCs and mobile phones equipped with Bluetooth. Announced Thursday, the suit claims a violation of Wi-LAN's U.S. Patent No. 5,515,369. Issued in 1996, patent covers a "method for frequency sharing and frequency punchout in frequency hopping communications network" – means the patent’s for a tec by which wireless systems such as Bluetooth avoid interfering with other wireless systems such as Wi-Fi, which operate in an unlicensed frequency, according to Tyler Burns. The filing shows also that patent was issued to Metricom, once famous for launching one of first wireless Internet services, known as Ricochet, before going bankrupt almost 10 years ago. But when asked about the connection between Metricom and Wi-LAN, Burns declined to comment.