NEW YORK (AP) — When the National Labor Relations Board ruled in 2016 that graduate teaching and research assistants have the right to unionize, it paved the way for union elections at Columbia, Yale, the University of Chicago and other schools.

But Columbia announced last week that it won’t bargain with the graduate students who voted for union representation.

Experts say administrators there and at other schools may be anticipating that a pro-management NLRB stocked with appointees of Republican President Donald Trump will reverse itself and rule that graduate students are not workers.

Other universities that have filed appeals rather than negotiating with teaching and research assistants may also be waiting for the labor board to issue a new ruling.