DOVER, Del. (AP) — A federal judge has ruled that a lawsuit against the University of Delaware over its campus shutdown and halting of in-person classes because of coronavirus can proceed as a class action on behalf of thousands of students who were enrolled and paid tuition in spring 2020.

The ruling notes that more than 17,000 undergraduates were enrolled at the time, and the university collected more than $160 million in tuition.

The plaintiffs say that before the pandemic, the school treated in-person and online classes as separate offerings and charged more for some in-person programs than for similar online classes.

They are seeking partial refunds of their spring 2020 tuition.