The National Labor Relations Board ruled Tuesday that student teaching and research assistants at private universities are employees and have a right to be represented by unions.

The 3-1 ruling overturns a 2004 NLRB decision that said graduate students were not employees covered by the National Labor Relations Act.

Tuesday's decision in a case involving graduate students at Columbia University potentially affects graduate students at hundreds of private colleges and universities throughout the U.S. Graduate students at many public universities, which are covered by state labor laws, are already unionized.

Columbia said in a statement that it disagrees with the ruling because it believes that the relationship between students and academic departments is not the same as the one between employee and employer. "First and foremost, students serving as research or teaching assistants come to Columbia to gain knowledge and expertise, and we believe there are legitimate concerns about the impact of involving a non-academic third party in this scholarly training," Columbia said.

While Columbia and other universities have long argued that collective bargaining could intrude on the educational relationship between graduate students and universities, the NLRB said in Tuesday's decision that such arguments are "unsupported by legal authority, by empirical evidence or by the board's actual experience."

Olga Brudastova, a graduate research assistant in civil engineering at Columbia, said she looks forward to "a speedy, fair election" for union representation.

"We instruct classes, grade papers for thousands of students and push the boundaries of research and the arts, but despite these contributions and more, Columbia administrators have stood in the way of our rights," Brudastova said.

The United Auto Workers is seeking to represent graduate teaching and research assistants at Columbia.