TAIPEI -(Dow Jones)- BT Group PLC (BT) filed a patent-infringement lawsuit against MediaTek Inc. (2454.TW) in a U.S. court, Sophia Liang, a spokeswoman for Taiwan's largest chip designer, said Thursday.
MediaTek didn't use the chip patent held by BT, Liang said, adding that the patent in question expired in October.
A Hong Kong-based public relations official at BT wouldn't immediately comment on the matter.
-By Jessie Ho, Dow Jones Newswires; 88622 502-2557; jessie.ho@dowjones.com