Graduate student teachers and research assistants at private universities like Yale are now permitted to form unions, the National Labor Relations Board ruled Tuesday in a landmark decision.

At the heart of the decision was a ruling on whether graduate students are primarily students or employees. The case concerned whether graduate students at Columbia could unionize, but applies to private universities nationwide.

“The board has the statutory authority to treat student assistants as statutory employees, where they perform work, at the direction of the university, for which they are compensated,” states the NLRB majority opinion.

Tuesday’s decision overturned a 2004 NLRB ruling on Brown University students stating that graduate students could not be considered employees. The board this week ruled 3-1 in favor of unionization, signaling a victory for Local 33, formerly known as GESO, which has lobbied for graduate student unionization at Yale for decades.

The decision leaves the fate of Yale’s pro-union graduate students uncertain. In a Tuesday afternoon email to the Yale community, University President Peter Salovey stressed his disagreement with the ruling — a stance that the administration has consistently taken regarding graduate student unionization. In February, Yale filed an amicus brief against graduate student unionization with the NLRB.

“We’re ecstatic,” said Local 33 Chair Aaron Greenberg GRD ’18. The organization is ready to “work out the terms of an election” — in which Yale graduate and professional students could vote on whether to form a student union — “win that election, and negotiate a contract,” he said.

“The question now is if President Salovey will sit down with us,” Greenberg said.

In his campus-wide email, Salovey wrote that the NLRB decision presents an opportunity to engage in a “robust discussion about the pros and cons of graduate student unionization,” calling on all community members to conduct discussions that are free from intimidation and pressure. Salovey also noted that the NLRB has changed its verdict on the issue for the third time in 16 years.

Tuesday’s ruling effectively swept aside the longstanding argument from private universities that graduate student unions would degrade the educational relationship between students and teachers. Such arguments are “unsupported by legal authority, by empirical evidence, or by the board’s actual experience,” according to the ruling.

Instead, the board cited a study of Columbia’s unrecognized graduate student union that suggested unionization was neither harmful nor beneficial to educational relationships or integrity.

“This decision recognizes that our work is work,” said Local 33 Co-Chair Robin Canavan GRD ’18.

The political makeup of the NLRB may have swung the vote this year. Board members are appointed by sitting U.S. presidents. The usual five-member board is now down to just four members, three Democrats and one Republican.