Rider University has been hit with a suit over its plans to undo its 1992 merger with Westminster Choir College of Princeton and to sell the music school and its campus.

The suit, filed Tuesday in the U.S. District Court for the Southern District of New York, seeks a declaration that Rider's plans to divest itself of Westminster violate the terms of the merger agreement. The 10 plaintiffs include students, parents, alumni and the two surviving Westminster trustees from the pre-merger period.

The plaintiffs claim Rider wants to sell Westminster's 23-acre campus, whose market value is estimated at $40-60 million, to shore up the university's finances. But using Westminster's assets to fund Rider would violate the intent of the choir college's trustees when they agreed to hand over the school to Rider, said Bruce Afran, the Princeton attorney who filed the suit.