 Shares of online-education company 2U Inc. TWOU, -13.73 were plunging in Wednesday morning trading after Piper Sandler analyst Arvind Ramnani downgraded the stock to underweight from neutral, citing multiple headwinds facing the industry and business model. Ramnani is concerned about regulatory risk as it relates to the companys revenue-share agreements, the possibility of digital-learning fatigue, and the potential for the companys university partners to insource management of online programs. 