Taiwanese smartphone maker HTC Corp. confirmed on Wednesday that it had filed a new patent lawsuit against rival gadget maker Apple in London, Britain.

The new lawsuit was filed on July 29 in London, with Chancery Division of the High Court of Justice, which deals with intellectual property & company law matters.

In the complaint, the Taiwanese firm has asked the court to reconsider the validity of Apple's patents. However, it is still unclear which patents are being targeted.

HTC’s move followed the U. S. International Trade Commission’s preliminary ruling favoring Apple in S3 Graphics patent claim. The U. S. Commission recently ruled that Apple’s Mac OS X system had violated two S3 texture compression patents, but it freed the Cupertino firm’s iOS-based iPhone and iPad from allegations that they infringe on patents of S3 Graphics, which is now in the hands of HTC.

HTC acquired S3 Graphics on July 6 for $300 million to expand its patent portfolio.

HTC and Apple have been locked in a legal wrangle since March last year, when Apple dragged the Taiwanese handset maker to court, accusing it of infringing on its as many as 20 patents.