An Internet leak occurs when a party's confidential information is released to the public on the Internet. Various types of information and data can be, and have been, "leaked" to the Internet, the most common being personal information, computer software and source code, and artistic works such as books or albums. For example, a musical album is leaked if it has been made available to the public on the Internet before its official release date. Many albums such as 10,000 Days, Toxicity II and Ugly Is Beautiful have been leaked on the internet.
End-of-life leaks by developers
Sometimes software developers themselves will intentionally leak their source code in an effort to prevent a software product from becoming abandonware after it has reached its end-of-life, allowing the community to continue development and support. Reasons for leaking instead of a proper release to public domain or as open-source can include scattered or lost intellectual property rights. An example is the video gameFalcon 4.0 which became available in 2000; another one is Dark Reign 2, which was released by an anonymous former Pandemic Studios developer in 2011. Another notable example is an archive of Infocom's video games source code which appeared from an anonymous Infocom source and was archived by the Internet Archive in 2008.
Other leaks
In late 1998, a number of confidential Microsoft documents later dubbed the Halloween documents were leaked to Eric S. Raymond, an activist in the open-source software movement, who published and commented on them online. The documents revealed that internally Microsoft viewed free and open-source software such as Linux as technologically competitive and a major threat for Microsoft's dominance in the market, and they discussed strategies to combat them. The discovery caused a public controversy. The documents were also used as evidence in several court cases.
Nintendo's crossover fighting video game series Super Smash Bros. has a history of having unconfirmed content leaked. Every game since 2008's Super Smash Bros. Brawl has been affected by leaks in some form:
*Super Smash Bros. Brawl for the Wii was leaked by a video on the Japanese language wii.com website, revealing unconfirmed playable characters on January 28, 2008.
*Super Smash Bros. for Nintendo 3DS and Wii U was afflicted in August 2014 by the "ESRB leak", where many screenshots and limited video footage of the 3DS version were leaked by a supposed member of the ESRB. The leak gained traction very quickly due to the screenshots mostly containing elements that the game ratings board would be interested in, such as trophies of suggestively-dressed female characters.
*Super Smash Bros. Ultimate was leaked in its entirety two weeks before its release, allowing many to play and datamine in advance. While the entire roster of characters and stages had already been officially revealed, many unrevealed collectibles, music tracks, and story elements were discovered and distributed. This prompted Nintendo to issue copyright strikes to many YouTube and Twitch channels.
Several high-profile books have been leaked on the Internet before their official release date, including If I Did It, Harry Potter and the Deathly Hallows, and an early draft of the first twelve chapters of Midnight Sun. The leak of the latter prompted the author Stephenie Meyer to suspend work on the novel.
On January 31, 2014 the original uncensored version of the South Park episode "201" was leaked, when it was illegally pulled from the South Park Studios servers and was posted online in its entirety without any approval by Comedy Central. The episode was heavily censored by the network when it aired in 2010 against the will of series creators Trey Parker and Matt Stone, and was never formally released uncensored to the public. The episode was the second in a two parter and was censored after the airing of the first part as a result of death threats from Islamic extremists who were angry of the episode's storyline satirizing censorship of depictions of Muhammad.
On March 13, 2016, the full list of qualifying teams and first round match-ups for the 2016 NCAA Men's Division I Basketball Tournament leaked on Twitter in the midst of a television special being broadcast by CBS to officially unveil them. The leak exacerbated criticism of a new, two-hour format for the selection broadcast, which was criticized for revealing the full tournament bracket at a slower pace than in previous years.
