That is quite a price for a young filly.

http://auctions.bloodhorse.com/viewstory.asp?id=34345

King Kamehameha Filly Smashes World Auction Record for Foal in Japan
by Deirdre B. Biles
Date Posted: 7/11/2006 2:47:34 AM
Last Updated: 7/11/2006 8:19:01 AM
A strapping filly from the first crop of the Kingmambo stallion King Kamehameha smashed the world record for a foal or weanling sold at public auction Tuesday in Japan.
Her price soared to 600 million yen ($5,217,391) during the opening session of the Japan Racing Horse Association select foal sale at the Northern Horse Park. Nobutaka Tada of Globe Equine Management Co. was the buyer, fighting off strong challenges from Dr. Riki Takahashi of Sheikh Mohammed's Darley Japan and Fusao Sekiguchi, who raced Kentucky Derby (gr. I) winner Fusaichi Pegasus.