Facebook staff uses the word "whales" to describe underage users who have spent huge amounts of money using their parents' credit cards to play games on their platform.
Facebook is letting children create huge accounts on its games, despite suspecting that they are minors, under the legal age of 13, according to court records.
Mark Zuckerberg's social network also knew that the average age of Angry Birds players was just five years old.
The network refused, when asked, to cancel a £5,000 account that a young boy had charged to his parents' card to make purchases on another game.
Two employees of the company, discussing the child's age and whether he was under the age of 13, refer to him as a "whale," a term used for big casino players.
The files, from a lawsuit filed in 2012, were revealed to the American Center for the Investigation of Complaints.
Parents expected guarantees and protections to stop in-game purchases, but the company did not refund their money. This situation led one company employee to say that Facebook had created a monstrous system.
Some employees raised concerns, but they appear to have been ignored.
