http://money.cnn.com/2017/09/15/media/facebook-mueller-ads/index.html
Facebook gave Mueller and his team copies of the 3,000 ads it discovered on its site linked to a Russian troll farm, as well as detailed information about the accounts that bought the ads and the way they were targeted, a source with knowledge of the matter told CNN.
The disclosure, first reported by the Wall Street Journal, may give Mueller's office a fuller picture of who was behind the ad buys and how the ads may have influenced voter sentiment during the 2016 election.
Facebook did not give copies of the ads to members of the Senate and House intelligence committees when it met with them last week on the grounds that doing so would violate their privacy policy, sources with knowledge of the briefings said. Facebook's policy states that, in accordance with the federal Stored Communications Act, it can only turn over the stored contents of an account in response to a search warrant.
"We continue to work with the appropriate investigative authorities," Facebook said in a statement to CNN.
Facebook informed Congress last week that it had identified 3,000 ads that ran between June 2015 and May 2017 that were linked to fake accounts. Those accounts, in turn, were linked to the pro-Kremlin troll farm known as the Internet Research Agency.