The state has dismissed a claim by some University of Minnesota graduate assistants that the university interfered with their attempts at unionization.
The graduate-assistant group lost a March vote on whether to unionize, 38 percent for to 62 percent against.
The students and their representative, the United Auto Workers, filed a charge of unfair election practices alleging the university tried to stifle student talk of unionization on campus.
They allege the university sabotaged their attempts by "targeting and restricting" union organizing last fall, and had continued through the election.
But Bureau of Mediation Services Commissioner Josh Tilsen saw no proof that any university actions interfered with the results of the election.
"There wasn't sufficient evidence to show that whatever conduct there was affected the outcome of the election," Tilsen said.
It was the fifth time graduate assistants tried to unionize over pay and working conditions.