Free ISP NetZero Friday brought suit against AT&T’s WorldNet service and its partner Predictive Networks, charging that the companies are infringing on its patent for an on-screen window displaying links and advertisements.
The Westlake Village, Calif.-based ISP filed the suit in a U.S. District Court in Los Angeles.
NetZero was awarded a patent for its ZeroPort technology, which displays advertisements outside of a browser window, on Dec. 5, 1999, and has since set about defending it vigorously.
Late last month it filed a lawsuit against Silicon Alley-based archrival Juno Online Inc., alleging infringement of the same patent. Juno responded to the lawsuit with a counter suit which alleged that NetZero was in fact infringing on its patented ad-banner technology. NetZero appeared to gain the upper hand in that confrontation last Friday when a judge issued a temporary restraining order against Juno pending the outcome of the case.
NetZero declined to comment on its lawsuit against AT&T WorldNet and Predictive Networks. AT&T could not be reached for comment as of this writing.