"This is a classic example of what is wrong with the U.S. patent system," Clarke said. "For someone to get a patent on something that is so obvious really just beggars belief." Freenet is not a commercial song-swapping network and did not receive a letter from Altnet.
Hadley, the Altnet counsel, said a federal jury has already upheld the validity of at least one of the patents. In 2000, one of the original patent holders -- a San Francisco firm called Digital Island Inc. -- sued Web content manager Akamai Technologies Inc., claiming that the company was violating the hashing patent. Akamai prevailed in the ensuing trial when a jury decided that the company was not using the technology. But the same panel concluded that the patent itself was valid, Hadley said.
Altnet licenses the patents from Ronald Lachman, a Northbrook, Ill., technology entrepreneur. Lachman, who has started several high-tech firms, was appointed chief science officer at Brilliant Digital in 2003. He declined to provide details of the licensing agreement.
Louis Tatta and Greg Bildson, the chief operating officers of Free Peers and Lime Wire, respectively, said they're in talks with their peers in the field about pooling resources to mount a legal challenge against the patent claims. Both said they would not honor Altnet's claims.
"When I stopped laughing, I reread the letter, and first of all I found it amusing that they said I was using their technology when we haven't even launched yet and nobody's seen my software," said Wayne Rosso, chief executive of Mashboxx, a soon-to-be-launched commercial peer-to-peer service. Mashboxx plans to distribute legal, licensed files over its network.
This is not the first time Altnet has asserted its patents. In December, Altnet and Brilliant Digital sued the Recording Industry Association of America and three companies that the record industry pays to track and disrupt the transmission of copyrighted songs over peer-to-peer networks. Altnet and Brilliant Digital claimed that the technology the companies were using to disrupt the system violated their hashing patents. A spokesman for the RIAA declined to comment.
Benjamin Hershkowitz, an intellectual-property attorney at Kenyon & Kenyon in New York, said the letters are consistent with an effort to profit from the technology rather than prevent people from using it. "If you wanted to keep your technology exclusive to you, you try to shut people down by getting an injunction."
David McGuire is a staff writer for washingtonpost.com. Washingtonpost.com staff writer Robert MacMillan contributed to this report.
