On July 17, 2018 the Honorable Jon S. Tigar of the United States District Court for the Northern District of California certified a class of investors who purchased or otherwise acquired Twitter, Inc. common stock from February 6, 2015 through July 28, 2015. Plaintiffs allege that Twitter, Inc. concealed declining user engagement and user growth. Professor Steven Feinstein of Babson College and Crowninshield Financial Research provided expert reports on market efficiency and whether damages can be computed for the Class.

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