The US International Trade Commission (ITC) postponed the completion date of its investigation into HTC following a complaint from Apple, which was due yesterday.

Observers have noted the decision will be significant because it will mark the first final verdict from any judicial entity in Apple’s numerous legal actions against Android device makers. The iPhone maker has been particularly active against Samsung, and also has actions open against Motorola Mobility.

The watchdog is now targeting completion on 14 December, an extension of eight days.

The ITC issued an initial determination in July 2011 which found a violation, and on 15 September 2011 it decided to review “several issues regarding each of the four asserted patents.” The case was the first of several filed by Apple and HTC with the ITC, and was originally initiated in March 2010.

The ITC has also issued an initial determination in a separate case, finding that Apple has not infringed four HTC patents asserted.  A review in this instance is expected to take place in February 2012.

It was revealed earlier this year that Google had assigned a number of patents to HTC, which had then been used to sue Apple. It also acquired patents from ADC Telecommunications, which have been asserted against the US smartphone giant.

HTC also announced a decision to acquire S3 Graphics, a company which holds patents allegedly infringed by Apple, although recent judgements in favour of Apple are believed to have weakened the appeal of this portfolio – HTC said it is now conducting a “holistic” review of the transaction.