Lawyers for Morrison & Foerster claim that the firm's track record of hiring, promoting and supporting women and working parents undermines a lawsuit which claims the firm discriminates against mothers and pregnant women.

Three female associates based in California sued MoFo last year for gender discrimination, alleging in a putative class action complaint that the firm routinely holds back mothers and pregnant women, pays them less than their male peers, and offers them fewer promotion opportunities. Three additional plaintiffs, including one who worked in the firm's Washington, D.C., office and another who worked in New York, joined the lawsuit last month.

On Friday, MoFo's lawyers at Gibson, Dunn & Crutcher made their first formal pushback against the suit, filing the firm's answer to the complaint and a motion for a judgment on the pleadings in the cases of two of the new plaintiffs.