File-sharing applications work by making selected files on a user's computer available for upload by anyone else using similar software, which in turn gives the user access to selected files on the computers of other users on the peer-to-peer P2P network.
Individuals with a personal computer and access to the Internet began to offer digital copies of recordings for download by other users, an activity known as file sharing, in the late 1990's using a program called Napster. Although record companies and music publishers successfully obtained injunctive relief against Napster's facilitating the sharing of files containing copyrighted recordings, millions of people in the United States and around the world continue to share digital .mp3 files of copyrighted recordings using P2P computer programs such as KaZaA, Morpheus, Grokster, and eDonkey.
Unlike Napster, which relied upon a centralized communication architecture to identify the .mp3 files available for download, the current generation of P2P file sharing programs allow an Internet user to search the .mp3 file libraries of other users directly; no website is involved. To date, owners of copyrights have not been able to stop the use of these decentralized programs.
There have been two broadly used file-sharing technologies. The first, a client-server structure, is an older system. It uses a network with a central computer (host computer) that serves users by allowing them to store (upload) or collect (download) files. The drawbacks of this system are reputed to be its capacity (bandwidth) and its vulnerability. Napster was one example of this type of system.
More recently, file-sharing software based on peer-to-peer technology was developed. This technology allows files to be transferred between end-user computers which are on an equal footing with each other, i.e. neither has the role of client or host computer. There is no central computer in a network based on this technology. Grokster was one example of this type of system.
- See A&M Records, Inc. v. Napster, Inc., 284 F.3d 1091 (9th Cir. 2002) (full-text); A&M Records, Inc. v. Napster, Inc., 239 F.3d 1004 (9th Cir. 2001) (full-text).
- See John Borland, "File Swapping Shifts Up a Gear" (May 27, 2003) (full-text).
- See Douglas Lichtman & William Landes, "Indirect Liability for Copyright Infringement: An Economic Perspective," 16 Harv. J.L. & Tech. 395, 403, 408-09 (2003).
- See Metro-Goldwyn-Mayer Studios, Inc. v. Grokster, Ltd., 259 F.Supp.2d 1029 (C.D. Cal. 2003) (full-text) (holding that Grokster was not contributorily liable for copyright infringement by users of its P2P file sharing program).