OAKLAND, Calif. (AP) — Facebook said Friday that it will flag all "newsworthy" posts from politicians that break its rules, including those from President Donald Trump.

Separately, Facebook's stock dropped more than 8%, erasing roughly $50 billion from its market valuation, after the European company behind brands such as Ben & Jerry's and Dove announced it would boycott Facebook ads through the end of the year over the amount of hate speech and divisive rhetoric on its platform. Later in the day, Coca-Cola also announced it joined the boycott for at least 30 days.

CEO Mark Zuckerberg had prev...