J. Paul Reddam, who hails from Windsor, Ont., made his comments in a blog appearing on the bloodhorse.com website. He writes there were two offers from U.S. breeding operations, one valued at just under $5 million, the other at $3 million.
"Certainly greed has something to do with it," he wrote, adding that the "one offer was four times higher in cash than the best offer here," and "I couldn't rationalize not selling him overseas."
Reddam also notes that the rights of Derby and Preakness runner-up Bodemeister "recently purportedly sold for about 13 million in America."
I'll Have Another was retired with a tendon injury the day before he was to run in the Belmont Stakes and attempt to become the first Triple Crown champion in 34 years.
The colt made a farewell appearance at Betfair Hollywood Park on Saturday before heading to a career at stud at Shigeyuki Okada's Big Red Farm on the island of Hokkaido.