SAN FRANCISCO (AP) — An attorney who brought an antitrust lawsuit against the NCAA is requesting more information about a letter Pac-12 presidents sent to leaders of the four other major football conferences proposing sweeping changes to the collegiate model.

Michael Hausfeld sent a letter to Arizona State President Michael Crow on Thursday asking what voice athletes would have under the Pac-12’s proposed reforms. Hausfeld’s law firm released a copy of the letter.

The Associated Press first reported details of the Pac-12 presidents’ letter Tuesday. The story included comments from Crow.

Hausfeld is representing former UCLA basketball star Ed O’Bannon and 19 other former athletes who claim the NCAA unlawfully profits off of athletes while restricting their ability to earn income while in college.

Hausfeld and Crow did not immediately respond to messages seeking comment.