Internet leak

An internet leak is the unauthorized release of information over 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.

Music leak

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 can include scattered or lost intellectual property rights. An example is the video game Falcon 4.0 which became available in 2000; another one is Dark Reign 2.

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, including 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.
November 2009: Climatic Research Unit email leak, aka Climategate
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.
2010 My Little Pony: Friendship Is Magic has been filled with lot of leaks for later seasons on scenes, leaked full song to the theme song, leaked early released episodes before they got aired on Discovery Family, unfinished episodes, 2018–present there was leaks for the generation 5 as My Little Pony: A New Generation was the start.
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.
In 2015, the unaired Aqua Teen Hunger Force episode "Boston" was leaked online. The episode was set to air during the fifth season as a response to a controversial publicity stunt for Aqua Teen Hunger Force Colon [Movie Film for Theaters] that occurred in the titular city, but Adult Swim was forced to pull it to avoid further controversy.
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.
On April 20, 2021, Apple supplier Quanta Computer was hit by a ransomware attack. The attackers began posting documents and schematics of MacBook computer designs as recent as March 2021. The attackers threatened to release everything they had obtained by May 1, 2021, unless a ransom had been paid, however nothing further came out of the breach.
On March 6, 2023, the unreleased film Scooby-Doo! and Krypto, Too!, a crossover involving Scooby-Doo and Krypto the Superdog was allegedly canceled, and was leaked online. It was alleged to be cancelled as tax write-off for parent company Warner Bros. Discovery's cost savings effort. On July 26, 2023, it was confirmed to not be cancelled, and a trailer was released on July 27, 2023 with a release date of September 26, 2023.
On May 6, 2023, a Twitter user leaked the trailer for the Five Nights at Freddy's film. Universal Pictures and Blumhouse worked to have videos of the trailer taken down.
On January 3, 2024, a Twitter user leaked the screenshots of 3 new minions and the plot for Despicable Me 4 weeks before the trailer launched and was claimed that it would appear at Super Bowl LVIII but screenshots were taken down by Universal and Illumination. Only two descriptions of the plot leak was confirmed true, while the third was false for Edith, Agnes and Margo were going to be teenagers. The trailer was released on January 28, 2024.
On September 18, 2024, an image of a Nintendo Switch 2 factory unit was posted online onto a Chinese website alongside a few CAD mockups of the console. When the Nintendo Switch 2 was revealed on January 16, 2025, the factory unit ended up being confirmed as true.
In March of 2025, the United States Department of Justice arrested Steven R. Hale, an employee of a multinational DVD company. Hale allegedly leaked the Blu-rays of the following titles; F9: The Fast Saga, Venom: Let There Be Carnage, Godzilla vs. Kong, Shang-Chi and the Legend of the Ten Rings, Dune, and Black Widow.