The US International Trade Commission (ITC) is to launch a formal investigation into a second patent infringement complaint by Apple against HTC, as the legal tussle between the companies takes yet another turn.
The ITC said in a brief statement issued on Monday that it will investigate "hardware and software used in a variety of portable electronic devices, including mobile communication equipment".
"By instituting this investigation, the USITC has not yet made any decision on the merits of the case. The USITC's chief administrative law judge will assign the case to one of the USITC's administrative law judges, who will schedule and hold an evidentiary hearing," the statement continued.
"The administrative law judge will make an initial determination as to whether there is a violation of section 337; that initial determination is subject to review by the ITC."
The ITC said that Apple has asked the organisation to issue HTC with cease and desist and exclusion orders, which would ban imports into the US of HTC devices alleged to infringe the patents.
The news comes after Apple appeared to be winning the original patent dispute with HTC currently before the ITC.
The Taiwanese handset maker reportedly said last month that it was willing to negotiate after an initial determination in Apple's favour brought the prospect of an import ban one step closer.
HTC is also prepared to appeal against the decision, but has seen its shares fall as a result of the ongoing disputes.
Apple, meanwhile, has opened legal disputes with several handset vendors in numerous geographies as the company seeks to protect its intellectual property and see off its rivals in the fiercly competitive smartphone market.
Last month, Apple asked the ITC for a similar ban on Samsung products being imported into the US, after Samsung requested the same of Apple devices in another acrimonious and long-running patent dispute.
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