NetZero Inc., Westlake Village, CA, a provider of free Internet service, sued AT&T's WorldNet Internet service for allegedly infringing on technology it uses to display advertisements and messages to customers while they are online.
The lawsuit, filed Jan. 12 in U.S. District Court in Los Angeles, accuses AT&T WorldNet and its partner, Predictive Networks, Cambridge, MA, of infringing on NetZero's patented zCast technology.
NetZero said it uses this technology through its Zero Port, which is a constant, on-screen window that serves as a navigational tool and also displays ads and customized messages while a user is online.
NetZero is seeking an injunction against AT&T and unspecified damages.
No one from AT&T or Predictive Networks was available to comment on the lawsuit.
NetZero on Dec. 27 sued rival Internet service provider Juno Online Services Inc., New York, for alleged infringement on its zCast patent.
On Jan. 12, NetZero received a temporary restraining order against Juno, preventing the free Internet service from displaying third-party advertisements in its ad banner window. Under the order, which runs until March, Juno can still use its ad banner window to display ads but can only advertise its own services, not a third party's.