https://www.theverge.com/2017/9/27/16376590/mark-zuckerberg-responds-to-president-trump

Facebook CEO Mark Zuckerberg has issued a public response to a tweet earlier Wednesday from President Trump, who claimed that the social network “was always anti-Trump” during the 2016 presidential campaign. “Trump says Facebook is against him. Liberals say we helped Trump,” Zuckerberg wrote. “Both sides are upset about ideas and content they don't like. That's what running a platform for all ideas looks like.”

Zuckerberg’s statement comes on the same day that Facebook, Google, and Twitter have been asked to testify before Congress on November 1st, where they’ll face questions about Russia’s meddling in the 2016 election and how it might have used their platforms to spread misinformation in an attempt to influence the outcome.