At least two companies that make smartphones and other devices have received subpoenas from a New York grand jury related to how they used Facebook user data that they received under deals with the social networking company. The companies were not named in the report.
These deals, which have mostly been discontinued, allowed people to access their Facebook accounts, or specific Facebook features, on platforms from other companies, including Blackberry and Windows Mobile phones.
In exchange, the platform providers got data about the users necessary to make these functions work. However, users did not always know the extent of the information collected and shared, according to the Times.
Facebook defended the deals after a Times report in December, noting that the data was shared to provide users with specific features — not for advertisers — and that they were publicized and scrutinized at the time.
Nonetheless, the fact that a grand jury is investigating them is serious, and shows how far the company has to go in order to regain the trust of users and regulators after two years of scandals related to privacy and security.
Responding to CNBC's request for comment, Facebook said: "It has already been reported that there are ongoing federal investigations, including by the Department of Justice."
"We are cooperating with investigators and take those probes seriously. We've provided public testimony, answered questions, and pledged that we will continue to do so," a spokesperson for Facebook said on email.
Earlier this month, Facebook CEO Mark Zuckerberg wrote that the company was pivoting toward a "privacy-focused" future, with an emphasis on features like disappearing messages and secure messaging.