The P2P model employed by Napster involved a centralized database that indexed a complete list of all songs being shared from connected clients.

Following Napster's demise, alternative decentralized methods of P2P file-sharing emerged, including LimeWire, Gnutella, Freenet, FastTrack, and BitTorrent.

[11] The release of MacStar's source code paved the way for third-party Napster clients across all computing platforms, giving users advertisement-free music distribution options.

This led to it being played on several radio stations across the United States, which alerted Metallica to the fact that their entire back catalogue of studio material was also available.

A month later, rapper and producer Dr. Dre, who shared a litigator and legal firm with Metallica, filed a similar lawsuit after Napster refused his written request to remove his works from its service.

In March 2001, Napster settled both suits, after being shut down by the Ninth Circuit Court of Appeals in a separate lawsuit from several major record labels (see below).

[12] In 2000, Madonna's single "Music" was leaked out onto the web and Napster prior to its commercial release, causing widespread media coverage.

[14] In that same month, with a court-ordered interim shut-down imminent, Napster went public with a settlement proposal which would have paid the record labels $1 billion over the next five years, with the money coming through a subscription service.

[17] In a 2018 Rolling Stone article, Kirk Hammett of Metallica upheld the band's opinion that suing Napster was the "right" thing to do.

[citation needed] One such musician to publicly defend Napster as a promotional tool for independent artists was DJ Xealot, who became directly involved in the 2000 A&M Records Lawsuit.

[21] Napster's facilitation of the transfer of copyrighted material was objected to by the Recording Industry Association of America (RIAA), which filed a lawsuit against the service on December 6, 1999.

[22] The legal action, while intended to shut down the service, brought it a great deal of publicity and an influx of millions of new users, many of whom were college students.

After a failed appeal to the Ninth Circuit Court, an injunction was issued on March 5, 2001, ordering Napster to prevent the trading of copyrighted music on its network.

[23] Lawrence Lessig claimed, however, that this decision made little sense from the perspective of copyright protection: "When Napster told the district court that it had developed a technology to block the transfer of 99.4 percent of identified infringing material, the district court told counsel for Napster 99.4 percent was not good enough.

A prototype solution was tested in 2002: the Napster 3.0 Alpha, using the ".nap" secure file format from PlayMedia Systems[26] and audio fingerprinting technology licensed from Relatable.

[28] Pursuant to the terms of the acquisition agreement, on June 3 Napster filed for Chapter 11 protection under United States bankruptcy laws.