Taiwanese smartphone maker HTC defended itself against a suit brought on by Apple yesterday, saying it doesn't infringe, but develops its own technologies.

HTC is not only a mobile technology innovator, [we] also hold a large number of patents, the company said in a filing to the Taiwan Stock Exchange on Wednesday.

The Taiwanese company, the world's largest maker of smartphones that use Google's Android mobile operating system, including the Nexus One, said it will work  with the U.S. justice system to protect its own innovations and rights.

Apple filed a lawsuit against rival handset maker HTC on Tuesday, over the alleged infringement of 20 patents related to the iPhone's user interface.

The patents at the center of Apple's lawsuits involve user interface technologies including icons, multi-touch and gestures, as well as technologies related to touch screens, power management, semiconductors, and the underlying hardware, software, and services architecture.

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, said Apple co-founder Steve Jobs in a statement.

HTC believes the Apple lawsuit poses a threat to its business in the short-term, HTC said. But some analysts believe this may prove to be a blow to companies like HTC vying to compete against Apple.

While this lawsuit could take years, we believe [Apple] may have a case here as the inventor of many key technologies including multi-touch and gestures, Kaufman analysts Shaw Wu said.

We think a likely outcome is an out-of-court settlement where some of the infringing features are taken out by HTC and/or licensing fees are paid to AAPL. In our view, competitors will likely need to work on alternatives.

The case is filed with the U.S. District Court in Delaware and the U.S. International Trade Commission (ITC).