The Recording Industry Association of America has withdrawn a lawsuit against four U.S. Internet service providers, saying it no longer needs to force the ISPs to block users' access to a rogue music file-sharing site that has since gone offline.

However, a separate action to force another ISP, Verizon Communications' Internet services division, to identify a user the RIAA accuses of online music piracy, lives on.

Thirteen record companies, including Arista Records, Interscope, Bertelsmann's RCA Records and AOL Time Warner's Warner Brothers filed suit last Friday against ISPs A&T Broadband, Cable & Wireless, Sprint Corp and UUNet Technologies, a unit of WorldCom.

Their copyright-infringement action sought to force the ISPs to block users' access to a China-based music file sharing site http://www.listen4ever.com, which it accused of pirating copyrighted works.

Because the site went offline not long after news of the suit broke, the RIAA decided to drop the action.

The RIAA said it had taken legal action "seeking the help" of ISPs to block access to www.listen4ever.com because "the site's particular file sharing network -- an especially flagrant and sophisticated violator of copyright laws, offering up a cache of copyrighted U.S. music with a centralized server, ala Napster -- had attempted to shield itself from U.S. laws by using offshore servers located in China."

Though hosted in China, the RIAA continued, "the site clearly targeted U.S. users with a polished, all-English website with music from U.S. top-selling artists, available for free." Hilary Rosen, chairman and CEO of the RIAA, called the www.listen4ever.com network "a crass attempt to evade our copyright laws by setting up shop in China while offering a treasure trove of mostly American music for free."

The RIAA also said the withdrawal of the lawsuit did not preclude it from further litigation if the site should decide to come back online, re-emerge under a new name or move to another server.

In a related action this week, the RIAA filed a motion to enforce a subpoena that was issued against Verizon's Communications' Internet services division on July 24th. Citing provisions in the Digital Millennium Copyright Act (DMCA), the RIAA asked a federal district court in Washington D.C. to enforce the existing subpoena, which seeks information related to "a computer connected to the Verizon network that is a hub for significant music piracy." The motion said Verizon is the only entity that can identify the infringer behind the computer.

Verizon has so far refused to comply with the subpoena. A Verizon spokesman said the company doesn't think the request meets the circumstances that the DMCA allows for in compelling information in order to protect against piracy.

"We recognize that copyright holders are entitled to protection, but we're also concerned about the privacy rights of our subscribers," said Eric Rabe, vice president of media relations for Verizon. "We want to make sure they're protected too," he added, particularly since this is a somewhat new area of law. Verizon is expected to file a response to the motion within a few days.