The Digital Millennium Copyright Act (DMCA) is a United States law passed in October 2000, based upon the "WIPO Copyright Treaty" of 20 December 1996. The DMCA increases the exclusive rights granted to copyright holders. The most controversial provisions impose criminal and civil penalties for distributing methods of breaking copy protection schemes.
On 24 October 2001, Sony threatened legal action against the site aibohack.com for allegedly violating the Digital Millennium Copyright Act by posting add-ons to Sony's Aibo software on his site.
"bnetd" is a program to run private servers for Blizzard's multiplayer games.

On 19 February 2002, Vivendi Universal Games/Blizzard Entertainment demanded the shutdown of bnetd.org, claiming their software violates the Digital Millennium Copyright Act (DMCA) by bypassing "anti-circumvention technology".

On 6 September 2000, the SDMI (Secure Digital Music Initiative) initiated a contest inviting people to break their "audio watermarking" technology intended to copy protect audio recordings.

Princeton University professor Dr. Edward Felten and his team did so, and planned to present their paper "Reading Between the Lines: Lessons from the SDMI Challenge" at the 4th International Information Hiding Workshop conference.

The RIAA (Recording Industry Association of America), the SDMI Foundation, and the Verance Corporation threatened a lawsuit under the DMCA (Digital Millennium Copyright Act) if he continued with presentation or publication of the paper.

Professor Felten and his team sued for a declaratory judgement that their report did not violate the DMCA, and questioning the law's constitutionality.

Google removed links to prominent anti-Scientology sites in response to a DMCA violation notice served to them by the Church of Scientology's lawyers.

Dmitry Sklyarov is a Russian programmer for Elcom. Elcom sells AEBPR (Adobe eBook Processor), a tool to remove restrictions from encrypted PDF files that prevent users from making fair uses, such as reading text with a speechreader, or printing. Sklyarov came to the United States to give a presentation at DefCon, a computer security conference, about weaknesses in Adobe's PDF encryption.

At Adobe's behest, the FBI arrested him for violating the DMCA (Digital Millennium Copyright Act). After protests and public outcry, Adobe publicly recommended Skylarov's release.

On 13 December 2001, the charges against Dmitri Sklyarov were dropped, with the condition that he return to testify in the criminal prosecution of his employer, Elcomsoft.