The Nintendo data leak, also known as the Nintendo Gigaleak, is a series of leaks of data from the Japanese video game company Nintendo on the anonymous imageboard website 4chan. The leak started in March 2018, but became most prominent in 2020. Ten main sets of data leaked on 4chan, ranging from game and console source code to internal documentation and development tools. The name "Gigaleak" mainly refers to the second leak on July 24, 2020, which was 3 gigabytes in size. The leaks are believed to have come from companies contracted by Nintendo in the design of these consoles, and/or from individuals previously convicted of intrusion into Nintendo systems. An earlier, much smaller leak had also occurred in 2018 which contained the Nintendo Space World 1997 demos for Pokémon Gold and Silver. A second large-scale leak around October 2024 named the Teraleak reportedly included the source code for Pokémon Legends: Z-A, Pokémon Winds and Pokémon Waves, and other assets for various Pokémon games.