Audience hit with pre-IPO lawsuit

May 7, 2012, 8:08 PM UTC

FORTUNE — Audience Inc. is expecting to go public this week, seeking to sell 5.27 million shares at between $14 and 416 a piece. But before pricing its IPO, expect the Silicon Valley company to submit an amended S-1 that includes mention of how it was recently sued for patent infringement.

The plaintiff is Dmitry Terez, who argues that Audience is violating his 2006 patent for pitch detection technology used in speech signaling. According to his suit, Audience uses Terez’s technology in audio processors used in more than 70 different mobile devices, including Apple’s (AAPL) iPhone 4s.

Terez does not appear to have ever filed lawsuits against anyone else, but the only other info I can find on him is that he used to work with a New Jersey company called SoundMath Technologies (ti’s website no longer works).

I’ve put in calls to both Terez and Audience, and will update this post if and when I hear back.

The case was filed last Tuesday in Delaware. Audience shareholders include Tallwood Venture Capital (32.75% pre-IPO stake), New Enterprise Associates (30.1%) and Vulcan Venture Capital (25 %).

Terez’s complaint is posted below:

[scribd id=92702467 key=key-13506lkgxicsr2722eyz mode=list]

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