Burst.com has filed a counter suit against Apple claiming that the iTunes software, the iPod and the Quicktime streaming software all infringe on patents held by Burst.com, the company announced on Monday.

After being approached by Burst.com in late 2004, Apple had filed for a declaratory judgment in January that it isn't infringing on Burst's patents, but Burst is going ahead with its lawsuit, filed on Monday in federal court in San Francisco. Burst is asking for royalties as well as an injunction, it said in a press release.

Burst has developed software that helps companies speed up the delivery of audio and video files over a network. It was involved in a similar patent infringement dispute with Microsoft last year that ended with a US$60 million settlement and a Microsoft licence to the Burst technology.

Apple and Burst had held discussions over the past year regarding the patents but never came to any licensing agreement. Apple doesn't believe the patents are valid, it said in January.

Richard Lang, co-founder, chairman and chief executive of Burst, said the company's patented technology involves the delivery of music or video over the Internet "faster than real-time". A television program over a broadcast network is delivered in real-time, meaning an hour-long show is delivered over the course of an hour. But Burst holds patents that cover sending an hour-long video across a network in a few minutes, in addition to other technology involved in delivering that video or audio content, he said.

Three of the four patents at issue in the new lawsuit are the same as the ones involved in the Microsoft suit, Lang said. An Apple representative did not immediately return a call seeking comment.