OMAHA, Neb. (AP) — Residential Capital is objecting to investor Warren Buffett’s offer to buy its mortgage division, but a bankruptcy judge will have the final say.

Residential Capital, which is also known as ResCap, filed a motion opposing a bid from Buffett’s Berkshire Hathaway Inc. late Thursday. ResCap’s parent company, Ally Financial Inc., filed a separate motion saying it was open to having Berkshire serve as the lead bidder on ResCap’s loan portfolio if the court believes the offer is better than Ally’s bid.