A group of prominent horse breeders, including several Rich Listers, have written to state racing ministers complaining about recent rule changes they claim could damage the multi-billion industry.

The group, including billionaire retailer Gerry Harvey and advertising identity John Singleton and their fellow Rich Lister Kevin Maloney, are objecting to recent changes by Racing Australia to have all thoroughbred horses – whether they race or not – to be governed by the rules of racing from birth. Another signatory is Newgate Stud Farm, part-owned by billionaire George Soros.