The FTC and 46 states filed an anti trust suit. The judge dismissed it on vague reasoning including that the plaintiffs had not shown that Facebook was a monopoly. Duh. Anybody knows that. I only picked up on this extraordinary fact by reading a piece in Wired, a less than reliable source. I did a search with Duck Duck Go and found supporting pieces in CNET and the Manchester Guardian. Funny, I never saw a single mention of this in the Wall St Journal, a paper to which I subscribe, and which you would think would be interested in this sort of thing. It might have been there and I missed it, but it probably was not there.
I have posted before that we ought to use the Sherman Anti Trust Act to break Facebook up into two of three pieces. Divide the assets, readers, posters, advertisers, shareholders, buildings, computers, cash evenly. Dunno what to do about Zuckerburg, we cannot cut him in half. This way the pieces have to compete with each other and if one piece does things the public or the advertisers do not like, they can move over to the piece that is more satisfactory. This ought to work better than any kind of regulation.