After years of delays, Columbia University has agreed to recognize the rights of graduate students to unionize - with some provisions. The agreement may have come when it did due to a planned strike on December 4, which would have affected the grading of final exams, and the university noted that the union may not strike until at least April 2020. The university also noted that any bargaining agreement must not impose on decision-making... "consistent with our educational and research mission." The United Auto Workers (UAW), which represents the students, have until November 28 to ratify the agreement, and talks with the students cannot begin later than February 25.
See "Columbia Recognizes Graduate Student Union, Ends Long Battle", Verena Dobnik, U.S. News and World Report, November 19, 2018