Microsoft has filed a lawsuit accusing a patent licensing company that attempted to sue it of breaching a contract between the pair.
Filing a lawsuit under seal, the Redmond-based company said Acacia Research has breached a contract regarding the licensing of more than 70 patents.
In 2010, Microsoft licensed 74 patents from Japanese web browser firm Access, via Acacia Research.
The licensing deal involved several patents relating to the Palm OS mobile operating system.
Acacia had already used the licences it held to file lawsuits against companies including Apple, Samsung and Motorola.
In October this year, it sued Microsoft in three separate lawsuits.
Microsoft's lawsuit, filed at the US District Court for the Southern District of New York on November 20, is in response to those lawsuits.
Acacia, which buys up large collections of patents in order to generate profits from licensing, has previously been described as engaging in patent troll type activity, a term sometimes used to describe non-practising entities which aggressively file lawsuits in hope of a pay-out.
“This is exactly the kind of allegation that many companies large and small make these days against so-called patent trolls,” said Florian Mueller, a patent consultant and author of the FossPatents blog in a post on the subject.
“There are patent reform proposals that Microsoft and other major patent holders including IBM do not support - they don't want to weaken the patent system as a whole because they consider it an engine of innovation.
“Microsoft has to fend off large numbers of patent troll lawsuits and has spoken out in favour of loser-pays fee-shifting and more transparency in patent ownership - reform measures that would discourage the kind of behaviour that Acacia is allegedly engaging in,” Mueller added.
In a statement, Microsoft deputy general counsel David Howard, said Acacia's lawsuits are the “worst kind of abusive litigation behaviour,” adding that the company was attempting to extract payment based on litigation tactics and not the value of its patents.
“Acacia is a very sophisticated company, and they would not have filed suit unless they thought Microsoft was not complying with the terms of the license,” said Jim Kulbaski, partner at Oblon Spivak McClelland, Maier & Neustadt, in Virginia, US.
“The question is did Acacia do something horribly wrong so that they deserve to be sued? We don’t know what that license agreement says, so we don’t know if Acacia is in the right or the wrong.
“It’s likely not a black or white situation.”
In recent months the US government has outlined several measures aimed at clamping down on troll-type activity.
Last week, WIPR reported that a subcommittee in the US House of Representatives had passed an amended bill aimed at making it harder for the companies to file lawsuits.
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