Broadcom Seeks Probe on Microtune Imports

Broadcom Corp., the biggest designer of semiconductor chips for cable modems, asked a U.S. trade agency to block rival Microtune Inc. from importing tuners, power amplifiers and other products to the U.S.

Broadcom asked the U.S. International Trade Commission to investigate whether Microtune, which makes radio frequency tuners used in cable modems and digital television sets, is importing products that are made using Broadcom’s patented technology.

Broadcom and Microtune have tussled in court for two years over which company invented circuits and other technology used in tuners. Jury selection began Monday in a Texas trial over Broadcom’s patents.

Shares of Irvine-based Broadcom fell 42 cents to $14.06 in Nasdaq trading. Plano, Texas-based Microtune shares rose 3 cents to $1.53 on Nasdaq.