Anti-piracy firms to join forces

Copy-protection company Reciprocal says it has struck an agreement with Britain's NetPD to help track down people infringing its customers' copyrights online. NetPD is one of several services that scours networks such as Napster, Gnutella and other lesser-known file-trading mediums for illegally copied MP3 and software files. The company first came to prominence when rock band Metallica used its services to find more than 200,000 Napster users trading the band's songs.

Reciprocal has helped provide customers--like Sony technology--that guard against copying, but has not previously mounted large-scale efforts to track down copyright violators online.