In closing at least one chapter in its book of legal battles with HTC (News - Alert), the U.S. International Trade Commission ruled this week that Apple (News - Alert) did not violate the smartphone maker’s patent, media reports said.

HTC subsidiary S3 Graphics initially brought the patent infringement investigation in 2010, claiming that certain Macs may have violated some of the patents claimed by S3, according to a report by ARS Technica.

S3 Graphics first brought its patent infringement complaint to the ITC in May 2010, with an administrative law judge (ALJ) determining in July 2011 that none of Apple’s mobile devices violated any S3 patents, according to media reports.

Specifically, the ALJ found that Apple computers utilizing an image compression format called DXT infringe claim 11 of the ’978 patent and claims 4 and 16 of the ’146 patent, according to the ITC.

In Sept. 2011, non-parties Advanced Micro Devices (News - Alert), Inc. and its subsidiaries ATI Technologies ULC and ATI International SRL filed a motion to terminate the investigation based on a claim that AMD (News - Alert) owned the patents at issue and declines to assert them in the investigation, ITC officials said. Apple then filed its own motion to terminate based on AMD’s patent ownership claims, therefore, the ITC extended the target date for completion of the investigation, ultimately ruling in Apple’s favor.

“Having examined the record of this investigation, including the ALJ’s final ID and the submissions of the parties and non-parties, the Commission has determined to reverse the ALJ’s finding of a violation of section 337 and find no violation,” wrote James R. Holbein, ITC secretary.

Previously, HTC had asked the trade commission to ban Apple from importing its iPhones, iPads and iPods, which it said violated the aforementioned patents, TMCnet reported.

HTC is not the only one going on the offensive in this battle. Apple has claimed that phones running on Google’s Android (News - Alert) mobile operating system violate patents for the iPhone, and has sued HTC in response. The Taiwanese company makes a number of Android-powered mobile devices.