Keeneland will handle the sale of a minority share of Curlin, the richest American racehorse ever.

The deadline is Nov. 5 for potential buyers to submit a sealed bid for the 20 percent stake in the 2007 Horse of the Year and Breeders’ Cup Classic winner.

A judge had ordered the minority share be sold to help satisfy a $42 million civil judgment against the horse’s minority owners, William Gallion and Shirley Cunningham.

In a separate criminal proceeding, they are accused of bilking clients out of millions in a settlement over the diet drug fen-phen. The first trial ended in a mistrial, and no date has been set for another one.

The 80 percent majority interest, held by Jess Jackson, isn’t affected by the sale. Jackson didn’t immediately return a call to his office Wednesday from The Associated Press.

Curlin will attempt to defend his title in the Breeders’ Cup Classic on Oct. 25. The horse recently passed Cigar by reaching $10.2 million in lifetime earnings in just two years on the track.

In a photo provided by Benoit Photo, Curlin is taken on a stroll around the grounds and paddock at Santa Anita in Arcadia, Calif., Wednesday, Oct. 15, 2008. Curlin will attempt to defend his title in the $5 millions Breeders’ Cup Classic horse race Oct. 25. (AP Photo/Benoit Photo)