https://www.reuters.com/article/us-retail-trading-sec/u-s-sec-suspends-trading-in-15-securities-due-to-questionable-social-media-activity-idUSKBN2AQ2VZ

The U.S. securities regulator on Friday suspended trading in the securities of 15 companies because of "questionable trading and social media activity," the latest in a string of temporary trading halts amid volatile trading in so-called "meme stocks."