AMD is being sued for patent infringement by holding company Opti.

Opti is one of a new breed of companies that exists only to enforce their patents and intellectual property through licensing deals and the courts. It also has prior form, having sued Nvidia in 2004 in a similar lawsuit and settled out of court earlier this year.

Opti claims that AMD has infringed three of its patents for a technology known as "Predictive Snooping of Cache Memory for Master-Initiated Accesses". The complaint alleges that AMD has infringed the patents by making and selling CPUs and core logic products using Opti's predictive snooping technology.

The three patents at issue in the lawsuit are US patent no. 5,710,906, 5,813,036 and 6,405,291 - the same three it alleged Nvidia has infringed.

Opti has filed the lawsuit with the District Court of Texas and asked for a jury trial. It is seeking an injunction and monetary relief. AMD has yet to respond.

Original reporting by IDG News Service