Record companies have joined the movie industry in trying to root out post-Napster file trading, putting new pressure on ISPs to clamp down on subscribers' actions. ISPs say the last few weeks have seen a sharp upturn in the number of requests they're getting to pull the plug on subscribers who are using file-trading software, such as Gnutella or iMesh. Driven by a combination of high-profile summer movie releases and a growth in the business of independent piracy hunters, these requests are putting service providers in an awkward position. Even as they avoid facing media-industry lawyers, these ISPs risk losing their customers to competing Internet access companies that may be less aggressive about curtailing the use of file-trading software. High-speed Internet provider, Adelphia, a cable company based in Pennsylvania, is one of the latest to join the list of ISPs cracking down on file swapping in the post-Napster world. Like many other ISPs, it has started suspending accounts of people who have been identified by record companies or movie studios as file swappers. "Over the past several weeks, the Adelphia Internet Abuse Investigation Team has seen a dramatic increase in the number of reports of copyright infringement," Michael Healy, the company's senior Internet abuse investigator, wrote in an e-mail to CNET News.com. "While Adelphia values its relationship with our customers, we must also take appropriate action when necessary to safeguard our interests in the global Internet community." Adelphia, like other ISPs offering high-speed Net service, is increasingly caught in a bind between protecting their customers and responding to the growing demands of copyright holders. Privately, ISP executives say that Napster and its rivals have been one of the biggest drivers of high-speed Internet use, a part of their business that most big ISPs are desperately trying to improve. But as decentralised swapping services like Gnutella, Music City's Morpheus and Kazaa emerge, copyright holders are leaning on ISPs to cut off file swapping at the source. ISPs have long received letters from record companies, or movie studios, about pirated works on their networks. But until the rise of Napster and similar services, the way to handle these was clearer. Under federal copyright law, an ISP is not liable for any copyright content posted on its network as long as it removes the content as soon as the owner points it out. Traditionally, movies, songs and software have been posted on the ISP's servers in the forms of pirate FTP sites or Web sites, and the ISP could simply pull these down. In the file-swapping world, the law has become murkier. People using Napster, Gnutella, or the others, keep all content on their hard drives, and the only way to block their actions is to turn off their connections. Some ISPs, such as Verizon Communications, have refused to go this far, calling it a "drastic remedy that infringes on people's rights and speech." The Motion Picture Association of America has been one of the biggest forces using these tactics. But individual studios are also boosting their efforts with ISPs. Twentieth Century Fox, for example, recently sent a notice telling service providers that distribution of any "Planet of the Apes" movie clips would be unauthorized, and that ISPs should pull them down. ISPs say this kind of announcement, before the release of a movie, is unusual, indicating just how seriously Hollywood is beginning to take online piracy. But the recent growth in threatening letters from the media industry is also coming from independent piracy hunters, such as MediaForce and Copyright.net, which contract with individual artists, labels or studios to hunt down versions of copyrighted works online. "We've sent out substantially more letters over the last several weeks, as more customers are interested in protecting their copyrights online," said MediaForce Chief Executive Aaron Fessler. He declined to give his customers' names, saying that most wanted to keep their involvement "hush-hush," wary of the backlash that met rock band Metallica after it publicly took a stand against Napster. But he said that one of the five largest major record labels has recently begun using his company's services. These independent companies operate automated systems that can troll file-swapping networks looking for their clients' work. Once they find it, it is a simple task to figure out the Internet address of the computer that is offering the content to the world. The companies then cross-reference this information with the ISP that owns that Internet address, and send a letter, showing exactly which files are being shared, demanding that the subscriber be stopped. Using this information, ISPs can figure out who was using that address at that time. Some, like Verizon, are resisting the demands, saying that copyright law does not force them to monitor or respond directly to content that is on their subscribers' hard drives. Others, like Adelphia, quickly cut off their subscribers' connections. Many, including DirecTV Broadband and Excite@Home, issue warning letters to their subscribers. If there is a second violation, the subscribers' accounts may be terminated for violating the ISPs' terms-of-service agreements, which generally bar using the networks for copyright violations. Excite@Home says most cases have stopped short of pulling the plug, and that only one person has been terminated. "It turns into an education opportunity," said Harris Schwartz, director of network policy and standards for Excite@Home. "In many cases, subscribers had no idea that they were doing anything wrong." Adelphia's Healy said the Recording Industry Association of America, the trade group that has pursued Napster and its rivals most vigorously in court, has not been as visible as the independent piracy hunters. But subscribers are nevertheless being targeted for trading songs. Former Adelphia customer, Tyrone Martin, was one of those targets. He had used Bearshare, a popular program that taps into the Gnutella network, to trade audio files online. Two weeks ago he found his connection turned off, and got a letter from his ISP saying the service had been suspended. Like many other customers receiving similar notices, Martin simply went elsewhere. "I told them where they could stick their modem and cable equipment, and proceeded to cancel my cable TV and modem accounts," Martin wrote in an e-mail to CNET News.com. "They are a communications provider. They are not censors or a government agency! Adelphia will never get another penny from me, and I hope others follow suit." 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