ITunes, iPods and QuickTime all infringe patents, claims Burst.com

Burst.com has added to Apple's courtroom troubles by filing a claim that iTunes, iPods and QuickTime infringe its US patents.

The latest move is actually a counterclaim in response to a suit filed by Apple in January seeking a declaration that Burst's patents are invalid and that Apple does not infringe them.

"We have a responsibility to protect our patents and to seek a fair return for the many years and tremendous investment in developing Burst technology and patents," said Burst.com chairman and chief executive Richard Lang.

Lang claimed that the company would rather not have to resort to litigation, but had to enforce its patent portfolio which had been developed over an 18-year period.

"Apple's actions have forced our hand and we now look to the courts to reaffirm Burst's rights as innovators and to be paid fairly for our widely acknowledged contributions to the industry," he said.

Burst alleges that Apple's iTunes music store, iTunes software, the iPod devices, and Apple's QuickTime streaming products infringe four of its US patents.

In March 2005, Microsoft settled a similar lawsuit with Burst by paying $60m for a non-exclusive licence to the company's patents.

Burst stated that its technology has been essential to Apple's success, but that Apple failed to license it when introducing the iPod and iTunes products in 2002.

Lang said that Apple may have assumed that Burst's patents would be invalidated during the court case with Microsoft.

The counterclaim was filed in Federal District Court in San Francisco on 17 April.