The Wigdor law firm on Tuesday sued Deloitte on behalf of a proposed class of women who said they were discriminated against after taking advantage of the Big Four accounting firm’s 16-week parental leave policy.

The lawsuit, filed in Manhattan federal court, claimed that employees who take their full leave had no right to return to their positions, despite assurances from the firm touting its generous policy, which exceeds the 12-week period covered by the federal Family and Medical Leave Act.