The probe follows a complaint filed by Singapore-based Creative Technology Ltd and US-based Creative Labs Inc that several handset makers have infringed on their patent, the ITC said in a statement.
The accused vendors are ZTE Corp, Sony Corp, Samsung, LG Electronics Inc, Lenovo Group Ltd, Motorola Mobility, HTC Corp and BlackBerry Ltd.
"The products at issue in the investigation are portable electronic devices, such as smartphones, with the capability of playing stored media files selected by a user from a hierarchical display," ITC wrote.
The trade panel said it has not yet made any decision on the merits of the case, and will decide a target date for completing investigation within 45 days after the institution of the investigation.
Creative Technology was not immediately available for comment. HTC said it cannot comment as the case has entered the court process.
Samsung and LG said they are looking into the case and didn't have any other immediate comment. Sony declined to comment. ZTE, Lenovo and other vendors were not immediately available.
"It's rare to see so many vendors involved in one patent infringement case," said research firm Canalys analyst Nicole Peng.
While the share price reaction of most Asia-based companies was muted, Hong Kong-listed shares of ZTE tumbled 11 percent on Friday to their lowest since July 2013. The Shenzhen-based company faced export restrictions imposed by the US Commerce Department in March for allegedly violating sanctions against Iran.
© Thomson Reuters 2016
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