Also see Let’s Clear Up a Few Things About Facebook’s Partners | Facebook Newsroom
"Facebook has been reeling from a series of privacy scandals, set off by revelations in March that a political consulting firm, Cambridge Analytica, improperly used Facebook data to build tools that aided President Trump’s 2016 campaign. Acknowledging that it had breached users’ trust, Facebook insisted that it had instituted stricter privacy protections long ago. Mark Zuckerberg, the chief executive, assured lawmakers in April that people “have complete control” over everything they share on Facebook.As Facebook Raised a Privacy Wall, It Carved an Opening for Tech Giants | NYT
But the documents, as well as interviews with about 50 former employees of Facebook and its corporate partners, reveal that Facebook allowed certain companies access to data despite those protections. They also raise questions about whether Facebook ran afoul of a 2011 consent agreement with the Federal Trade Commission that barred the social network from sharing user data without explicit permission."