Apple, Samsung, Sandisk sued over MP3

The suit, which came to light over the weekend, was filed on Feb. 16 in Marshall, Texas. The eastern Texas city is fast becoming one of the leading locations of patent infringement lawsuits in the U.S. thanks to speedy trials and juries that more often than not find in favor of the plaintiff.

In the complaint Texas MP3 Technologies alleges infringement on U.S. patent 7,065,417, which was awarded in June 2006 to multimedia chip-maker SigmaTel Inc. and covers "an MPEG portable sound reproducing system and a method for reproducing sound data compressed using the MPEG method."

Just over a month later SigmaTel said that it had sold the patent to a Dallas-based patent licensing agency because it believed the agency would be better able to take advantage of its potential value.

"Because these are such basic patents to digital music, we believe it will be difficult to design around these patents and have a commercially viable player," SigmaTel said in a statement when it announced the sale of the patent.

SigmaTel said it had retained international rights to the patent and has insulated its customers from any legal action associated with the patent.

Whether Texas MP3 Technologies is the Dallas-based company that bought the patents from SigmaTel or whether it acquired them from somewhere else is unclear. In its lawsuit Texas MP3 Technologies said it is the "assignee of all rights" of the patent and holds "all rights of recovery." The company listed an address in Marshall, Texas, in the complaint.

Texas MP3 Technologies is asking for a jury trial.