Apple has accused HTC that it has infringed 20 patents (owned by Apple) used in the iPhone. The infringements are related to technology used in the architecture and underlying hardware as well as the iPhone UI. As is widely known HTC manufactures handsets for many companies including Google and it is behind the Nexus One handset.

To put this in Apple boss Steve Jobs words: “We can sit by and watch competitors steal our patented inventions, or we can do something about it. We’ve decided to do something about it. We think competition is healthy, but competitors should create their own original technology, not steal ours.”

Apple has sought for an injunction in its legal filing, which could eventually bar sale of HTC phones that use the disputed technology in the US. The suit has been filed with the US International Trade Commission and a Delaware district court.

HTC has not responded yet. HTC has made several handsets based on the Android platform, the Google Mobile OS and has been in the limelight for designing the first handset branded by Google, Nexus One.

Meanwhile, Apple is already fighting a legal battle with the Finnish mobile giant, Nokia. Nokia sued Apple for infringing on its patents in October 2009. Apple filed a counter suit in December 2009 and Nokia fired another round of legal suits towards the end of 2009.