Facebook fought to keep a trove of thousands of explosive internal documents and emails secret. They were just published online in full.

• Thousands of pages of internal Facebook documents have been published, shedding new light on how the company profited off user data and grappled with rivals.
• The documentation was collected as part of a lawsuit involving Facebook and a developer it took action against, and subsequently leaked.
• Facebook has fought vigorously against the release of the documents, arguing that they presented an unbalanced picture of the company.
• Here are the key details you need to know about the unprecedented leak.

An explosive trove of nearly 4,000 pages of confidential internal Facebook documentation has been made public, shedding unprecedented light on the inner workings of the Silicon Valley social networking giant.

On Wednesday, investigative reporter Duncan Campbell released a vast swathe of internal emails, reports, and other sensitive documents from the early 2010s, that go into detail on Facebook's internal approach to privacy and how it worked with app developers and handled their access to user data.

The documents were originally compiled as part of a lawsuit that the startup Six4three brought against Facebook for cutting off its bikini-photo app's access to its developer platform. The documents were supposed to remain under seal - but have subsequently leaked out.

Some of the documents have already been made public prior to Wednesday. The British Parliament's Digital, Culture, Media and Sport (DCMS) Committee published hundreds of pages in a report in December 2018, after they were seized from Six4three's founder Ted Kramer when he visited the UK.

And in the months prior to putting the entire trove of documents into the public domain, Campbell shared them with journalists at NBC News and other outlets, who subsequently published a number of stories about them. (Campbell says that he was sent the documents in February 2019, the same day that the DCMS published its report. The sender was anonymous.)

Facebook has fought vigorously against the release of the documents. It continues to argue that the documents do not paint a balanced picture of its activities. In an emailed statement, a company spokesperson told Business Insider: "These old documents have been taken out of context by someone with an agenda against Facebook, and have been distributed publicly with a total disregard for US law."

Business Insider is combing through the documents, and will update this story with our findings.

Here are some of the key revelations from the document dump, including from reports published from earlier leaks:

• Facebook executives quietly planned a data policy "switcheroo." "Facebook began cutting off access to user data for app developers from 2012 to squash potential rivals while presenting the move to the general public as a boon for user privacy," Reuters reported on Wednesday, citing the leaked documents.
• Facebook considered charging companies to access user data. Documents made public in late 2018 revealed that between 2012 and 2014 Facebook was contemplating forcing companies to pay to access users' data. (It didn't ultimately follow through with the plan.)
• Facebook leveraged its volumes of user data to benefit its friends while deliberately kneecapping its competitors. NBC reported in April that "in some cases, Facebook would reward favored companies by giving them access to the data of its users. In other cases, it would deny user-data access to rival companies or apps."
• Facebook whitelisted certain companies to allow them more extensive access to user data, even after it locked down its developer platform throughout 2014 and 2015. TechCrunch reported in December 2018 that it "is not clear that there was any user consent for this, nor how Facebook decided which companies should be whitelisted or not."
• Facebook planned to spy on the locations of Android users. Citing the documents, Computer Weekly reported in February 2019 that "Facebook planned to use its Android app to track the location of its customers and to allow advertisers to send political advertising and invites to dating sites to 'single' people."

The leak includes nearly 4,000 pages of internal Facebook documents, nearly 3,000 pages of other exhibits from the case, and hundreds of pages of other pieces of legal documentation.

This story is developing...

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