Columbia University, Duke University, the University of Pennsylvania and 29 other elite U.S. colleges and universities were accused Friday in a proposed class action of conspiring to inflate tuition costs for tens of thousands of students through the popular "early decision" admissions process.

The lawsuit, filed in federal court in Boston by former students at Wesleyan University and two other schools, said colleges are using early-decision commitments to charge more for both early and regular-admission students.

Early decision students face earlier deadlines to apply to college but a greater chance of acceptance. They agree to attend if admitted, forfeiting future offers or aid packages from other schools.

The 32 defendants are violating antitrust law by agreeing not to compete with each other for early-decision students, the lawsuit said. The universities also mislead applicants by presenting early decision offers as legally binding, it said.

“Early decision applicants lose choice and negotiation leverage, while regular decision applicants are left to scramble for an artificially diminished number of admission slots doled out at lower acceptance rates,” said Benjamin Brown, an attorney for the plaintiffs.

The University of Pennsylvania and Columbia declined to comment. Duke, Vassar, Wesleyan and other defendants including Amherst, Northwestern, University of Chicago and Johns Hopkins University did not immediately respond to requests for comment.

The defendants also include the Consortium on Financing Higher Education, an organization of private liberal arts schools that helps facilitate information-sharing among them.

The consortium did not immediately respond to a request for comment.

The plaintiffs asked the court to grant class action status for early decision applicants since 2021 and some students who enrolled through the regular decision process. The lawsuit seeks unspecified monetary damages for tuition overcharges and to bar the use of binding early decision programs.