Internal emails at Facebook, including those involving Chief Executive Officer Mark Zuckerberg, were published online by a committee of U.K. lawmakers investigating social media's role in the spread of fake news.
The documents, which had been sealed by a California court, led lawmakers to conclude that Facebook undertook deals with third party apps that continued to allow access to personal data.
Damian Collins, head of the committee, added that Facebook shut off access to data required by competing apps, conducted global surveys of the usage of mobile apps by customers possibly without their knowledge, and that a change to Facebook's Android app policy that resulted in call and message data being recorded was deliberately made difficult for users to know about.
In one email, dated Jan. 23 2013, a Facebook engineer contacted Zuckerberg to say that rival Twitter had launched its Vine video-sharing tool, which users could connect to Facebook to find their friends there. The engineer suggested shutting down Vine's access to the friends feature, to which Zuckerberg replied, "Yup, go for it."
"We don't feel we have had straight answers from Facebook on these important issues, which is why we are releasing the documents," said Collins in a Twitter post accompanying the published emails.
"Like any business, we had many of internal conversations about the various ways we could build a sustainable business model for our platform," Facebook said in an emailed statement. "We've never sold people's data."
Collins said last week that he would release the emails and that he was free under U.K. law to do so. He'd obtained the documents after compelling the founder of U.S. software company Six4Three to hand them over during a business trip to London.
A spokesman for Facebook was unable to immediately comment.
Six4Three's founder, Ted Kramer, had obtained them as part of a legal discovery process in a U.S. lawsuit against Facebook that his company has brought against the social network in California.
Facebook touted itself as championing privacy four years ago when it decided to restrict outsider developers' access to data about its users' friends.
In one email, dated Feb. 4, 2015, a Facebook engineer said a feature of the Android Facebook app that would "continually upload" a user's call and SMS history would be a "high-risk thing to do from a PR perspective." A subsequent email suggests users wouldn't need to be prompted to give permission for this feature to be activated.
Kramer was ordered by a judge on Friday to surrender his laptop to a forensic expert after admitting he turned over the documents to the British lawmakers, in violation of a U.S. court order.
"What has happened here is unconscionable," California Superior Court Judge V. Raymond Swope said to Kramer and his attorneys during the hearing.
Facebook wants the laptop to be evaluated to determine what happened in the U.K., to what extent the court order was breached, and how much of its confidential information has been divulged to the committee.