HTC is going to appeal the ruling by a U.S. trade body which found the mobile phone manufacturer guilty for the infringement of two patents held by Apple Inc. Last year, Apple filed a complaint against HTC with the US International Trade Commission accusing it of violating ten patents related to the iPhone’s design and functionality.

“We are going to appeal. We are confident that we have a strong case,” said HTC Chief Financial Officer Winston Yung.

As part of its efforts to get back at Apple, HTC acquired S3 Graphics for $300 million in cash from VIA Technologies Inc. and WTI Investment International Ltd. The company said it expects the deal to strengthen its intellectual property portfolio and bring in benefits for HTC in its patent lawsuit with Apple.

As the legal battle between the rivals escalates, Apple filed a new complaint against HTC with the ITC on July 11, claiming that HTC was infringing on another five of its patents involving software architecture and user interfaces used in the iPad and iPhone.

HTC general counsel Grace Lei said in a statement that,“We strongly believe we have alternate solutions in place for the issues raised by Apple. We look forward to resolving this case.”

HTC continues to deny all allegations of Apple over its patents and is seriously planning to protect its intellectual property, which has been targeted by the American consumer giant since last year. Market observers said that Apple has lodged patent infringement lawsuits against HTC mainly because HTC has outperformed Apple in smartphone sales in the US market, in addition to the European and Asian markets.

HTC took the lead in selling its 4G LTE smart phone model to two major U.S. telecom carriers in 2010, Verizon and AT&T, causing sales of HTC smart phones in the U.S. to keep rising steadily over the past year.  HTC already sold 6 million smart phones in North America in the second half of the year alone, which is higher than the corresponding figure of 5.5 million units sold by Apple.

Patent lawsuits are a regular occurrence among technology giants, especially in this emerging mobile market.  Apple is facing some lawsuits of its own, now being sued by Nokia for patent infringement, and has fired back a countersuit against the Finnish mobile phone giant.  Last week Apple also hit back at an infringement claim by Samsung, calling for the South Korean company to be investigated.