Elizabeth Dwoskin

Facebook executives in recent years appeared to discuss giving access to their valuable user data to some companies that bought advertising when it was struggling to launch its mobile ad business, according to internal emails quoted in newly-unredacted court filings. In an ongoing federal court case against Facebook, the plaintiffs claim that the social media giant doled out people’s data secretly and selectively in exchange for advertising purchases or other concessions, even as others were cut off, ruining their businesses.

Facebook chief operating officer Sheryl Sandberg admitted that she had received information about the company’s work with Definers, the Republican-affiliated consultancy that conducted opposition research into Facebook’s critics. Her comments, written in a blog post the night before Thanksgiving, appeared to walk back her statements from the week of Nov 12 in which she said she did “not know” Facebook had hired Definers.

Facebook said it had removed more than a billion fake accounts and taken action against millions of posts, photos and other forms of content that violated its prohibition against hate speech, terrorist propaganda and child exploitation, the latest sign that the social-networking giant faces an onslaught of online abuse as it builds tools to spot it.

Gab has become the most visible of a collection of services catering to people mainstream companies such as Twitter and Facebook have rejected as too hateful, extreme or threatening in their posts as part of a crackdown on extremism.

For two years, Alex Stamos was the Facebook executive tasked with defending the company’s systems against Russian interference and other critical threats. Now the former chief security officer, who left the social network in Aug, says Facebook — and the entire technology industry — needs a systems of checks and balances to help it weigh the complex decisions Silicon Valley companies are making in areas including security and democratic expression.

Facebook said that it has purged more than 800 US publishers and accounts for flooding users with politically oriented content that violated the company’s spam policies, a move that could reignite accusations of political censorship. The accounts and pages, with names such as Reasonable People Unite and Reverb Press, were probably domestic actors using clickbait headlines and other spammy tactics to drive users to websites where they could target them with ads, the company said.

Online advertising systems regularly put mainstream ads alongside content from the political fringes — and dollars in the pockets of those producing polarizing and politically charged headlines. This mismatch of online content and ads, which digital advertising companies have been working to fix, goes to the heart of how the Internet economy works. Tens of billions of dollars are at stake in the promises of online ad systems to match advertising pitches with receptive targets.

Technology giants increasingly are casting themselves as defenders of online integrity as American democracy, yet again, comes under attack. A recent string of revelations from companies including Facebook, Microsoft and Google about foreign hacking and disinformation amount to a public answer to charges that the technology industry should have done more to thwart Russia’s online attacks in 2016.

Facebook has begun to assign its users a reputation score, predicting their trustworthiness on a scale from zero to 1. The previously unreported ratings system, which Facebook has developed over the past year, shows that the fight against the gaming of tech systems has evolved to include measuring the credibility of users to help identify malicious actors. Facebook developed its reputation assessments as part of its effort against fake news, Tessa Lyons, the product manager who is in charge of fighting misinformation, said in an interview.

At least three groups that Facebook banned recently for spreading disinformation shared similar names and traits with Twitter accounts that had been linked publicly to Russia earlier this year, underscoring the challenges of swiftly shutting down a foreign influence campaign even once strong hints emerge of who is behind it. Facebook’s handling of the situation underscores the nation’s struggles to respond to credible reports of disinformation two years after the first signs that Russians were seeking to manipulate the 2016 presidential election.