The U.S. Fifth Circuit Court of Appeals has sided with the American Quarter Horse Association (AQHA) in a long-running case involving the registration of cloned Quarter Horses.

Some owners have used the cloning process—which was first performed on horses in 2003—to preserve their animals’ bloodlines, particularly those of high-performance equines. In response to cloning as a way to preserve bloodlines, some breed associations ruled on whether or not cloned horses can be included in their breed registries.

In 2004 the AQHA board of directors approved Rule 227(a), which prohibits cloned horses or their offspring from being included in the organization’s breed registry. The AQHA opposed the registry of cloned animals on several grounds including that cloning does not improve the breed and that only the most elite horses may be cloned over and over again for use in breeding programs.

Subsequently Jason Abraham and two of his related companies, Abraham & Veneklasen Joint Venture and Abraham Equine Inc., filed suit against the AQHA asking the court to order the AQHA to remove Rule 227(a) on grounds that the ban on registering cloned horses and their offspring violates antitrust laws