https://www.techdirt.com/articles/20190714/01002842583/ftc-facebook-why-5-billion-fine-is-both-too-little-too-much.shtml

By now, you've certainly heard the news that was very likely leaked by Facebook late on Friday that the FTC, by a narrow 3 to 2 party line vote, had approved a $5 billion fine for Facebook for violating its earlier consent decree in the way it allowed an app to suck up lots of data that eventually ended up in Cambridge Analytica's hands. Most of the reaction to this fine (by far, the largest in the FTC's history) is anger.

Many people focused on one key point to argue that the fine wasn't enough: Facebook's stock jumped upwards after the news broke, to the point that Facebook's valuation probably went up more than the amount of the fine itself (never mind the difference between the value of equity and actual cashflow...). However, I wouldn't read too much into the stock jump. After all, Facebook had already said back in April that it was expecting a $5 billion fine, meaning that Wall Street had already priced in exactly that. If the $5 billion fine had come out of the blue it might have been a different story. The bump, then, could be explained by investors reacting to the end of any uncertainty and the fear that the fine might have been larger.