Apple has expanded its lawsuit against HTC. In a complaint filed Monday in the U.S. District Court for the District of Delaware, Apple accuses HTC of infringing two additional patents and re-asserts its allegations of infringement of two others, reports “All Things Digital” (

Apple filed in March against HTC for infringing on 20 Apple patents related to the iPhone’s user interface, underlying architecture and hardware. The lawsuit was filed concurrently with the U.S. International Trade Commission (ITC) and in U.S. District Court in Delaware.

As many as 10 of those violations involve the Nexus One, Apple said in a complaint submitted to the ITC. The Delaware lawsuit, however, didn’t specify the HTC-made phones that allegedly violated Apple’s patents.

Last month HTC, in turn, filed a complaint with the United States International Trade Commission (ITC) to halt the importation and sale of the iPhone, iPad and iPod in the U.S. HTC says Apple is infringing on five of its patents.