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A few months ago, source code for multiple versions of Metal Gear Solid 2: Sons of Liberty leaked online, containing "non-public videogame assets from MGS 2 and internal MGS 2 development materials."
And, unsurprisingly, Konami isn't happy.
Not only did it ask for "the infringing material" to be removed from 4Chan and two separate file-sharing websites (Pixeldrain and Buzzheavier), it has also now filed a lawsuit in a California court, hoping to “uncover the source of the leak and to ensure that similar or further public disclosures do not occur,” as discovered by Aftermath (and reported by Kotaku).
To do this, Konami has demanded that the file-sharing sites and message board "retain and segregate any data that may be useful for identifying the persons responsible for uploading or otherwise disseminating Konami’s content. This is in order so that ultimately "Konami may seek remedies from these persons and prevent any further or other violations of Konami’s rights." But, as it states, none of the sites has so far shown signs of cooperating with this as of the lawsuit’s filing on June 2nd, having failed to provide “information that would allow Konami to identify the culprits who uploaded and infringed Konami’s intellectual property.”
Important to note is that 4Chan, Pixeldrain, and Buzzheavier aren't defendants in the case. Instead, Konami has named the defendant(s) as Does (as in John or Jane Doe), hoping to discover the individuals' real identities as the lawsuit progresses.
Since its original release in 2001, Metal Gear Solid 2 has gone on to be regarded as one of the most influential video games of all time and has also been included on countless "Best Of" lists over the years. As a result, there has been a lot of interest from fans about learning more about how the game was put together, as well as scrapped and missing content from earlier builds.
As noted by Kotaku, the files included in the leak were dated 2007 (suggesting they may have come from the Metal Gear Solid HD Collection, which released in 2011) and included "an unreleased port of Metal Gear Solid 2: Substance, an expanded version of the game planned for the Nintendo Wii" and materials related to its iconic E3 demo and trailer.
As a result, when the source code leaked, many members of the game's community immediately jumped on these files to see what they could uncover, while modders attempted to restore missing and lost content to playable versions of the game.