(AP) -- Sony Corp. has filed a patent infringement complaint against LG Electronics Inc. and its U.S. subsidiaries with the U.S. International Trade Commission, saying LG's mobile phones and modems step on proprietary technology including photo-based caller ID.
Among the seven patents Sony cites is one that describes how phones associate photos with phone numbers, so that when someone calls a friend, for example, the caller's photo pops up on the friend's phone, according to commission documents made public Wednesday.
Sony also filed a lawsuit against LG in U.S. District Court in Los Angeles. The filing was not available online Wednesday and it was not known whether Sony made identical claims.
LG did not immediately return messages seeking comment.
The complaints are the latest in a long string of patent disputes among phone makers trying to stake a claim on a slice of the rapidly growing smart phone market. Apple Inc., Microsoft Corp., Nokia Corp. and HTC Corp. and others have taken legal action to protect intellectual property in the last few years.
In the International Trade Commission complaint, Sony also said LG infringes on patented technology for encoding and transmitting audio in ways that adjust to available bandwidth capacity; delaying the start of audio recording for a set amount of time so that the recording doesn't pick up inadvertent noises; and technology for using the images streaming through a device's camera as a real-time viewfinder, then switching to saving better-quality files when the user decides to snap a picture.
The other patents in question involve ways of divvying up bandwidth and handing off phone calls from one base station to another to make the best use of network capacity.
Sony listed LG's Fathom and Xenon phones and the LG VL600 modem, which can be used to connect a computer to the Internet using a cellular data connection, among other phones and devices.
In the commission filing, Sony said Nokia, Samsung Electronics Co. and Sony Ericsson, an LM Ericsson and Sony joint venture, license the patented technology in question.
Sony asked the International Trade Commission to block imports of products made with contested technology, but that doesn't mean sales of LG products are immediately threatened. Patent cases can take months or years to resolve, and agreements over licensing and royalty payments often emerge.
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