As the general horse-owning public becomes more knowledgeable about HYPP, Equine Legal Solutions receives more questions about disclosure of HYPP status in sales and purchases. Typically, the buyer has purchased a horse without any awareness of its HYPP status and has determined post-purchase that the horse is HYPP N/H. Sometimes, the buyer finds out after the horse begins to display HYPP symptoms. In other cases, the horse is not symptomatic, but the buyer is worried that the horse might develop symptoms.
Does the seller have a legal duty to disclose a horse's HYPP status at the time of sale? What responsibility does the buyer have to educate themselves about HYPP and other genetically-linked conditions, and have horses tested during a pre-purchase veterinary examination? In general, horse sales are buyer beware, but with one very important exception. The seller has a legal duty to disclose material facts about the horse that are known to the seller, especially defects.
Being N/H or H/H for HYPP is clearly a material fact in a horse sale. Note that this is true even if the horse has never suffered an "attack" or otherwise shown outward symptoms of HYPP. The materiality stems from several important factors. With the possible exception of certain halter horses, being an HYPP carrier, especially an H/H carrier, has a significant negative impact on the horse's fair market value. For mares and stallions intended for breeding, HYPP status is a vital consideration. To minimize the possibility of HYPP symptoms and maximize the horse's performance potential, veterinarians recommend certain diet restrictions. During an HYPP attack, a horse could injure itself or its rider or handler.
So, because HYPP is a material fact, if a seller is aware of a horse's HYPP status, the seller has a duty to disclose it to the purchaser prior to the sale. For example, if a seller has had the horse tested and the results are N/H, the seller has a duty to disclose such fact to the buyer.
In some situations where the seller is unaware of the horse's HYPP status, the seller may have reason to suspect the horse is a carrier. For example, a breeder may breed an N/H mare to an N/N stallion. Statistically, the odds of the foal being N/H are 50%. So, even if the breeder has not had the foal tested, as long as the breeder knows the mare is N/H, the breeder knows there's a good chance the foal is a carrier. At Equine Legal Solutions, this awareness creates a duty of disclosure to the foal's buyer.
If a horse has had an unexplained collapse episode or shows other symptoms that may be related to HYPP, the seller would have a duty to reveal such information to the buyer, even if they are unaware of the horse's actual HYPP status or the cause of the symptoms. The duty stems not necessarily from the possible link to HYPP, but rather from the fact that the horse has shown significant, unexplained symptoms that may have an important impact on its health.
Now, what responsibility does the buyer have? If the seller discloses possible symptoms of HYPP or the fact that the horse may be an HYPP carrier, the buyer should include an HYPP test as part of the veterinary prepurchase exam. If the buyer is knowledgeable about the existence of HYPP, the buyer should examine the horse's pedigree, and if "Impressive" is present, the buyer should have the horse tested for HYPP as part of the prepurchase exam. If there is any doubt about whether the horse might be a carrier, the buyer should have the horse tested for HYPP prior to purchase. If the seller makes proper disclosures (or has no knowledge or reason to know of the horse's HYPP status), and the buyer chooses not to test the horse for HYPP, the buyer then bears the risk that the horse is a carrier. Note that this is true even if the buyer is not knowledgeable about HYPP.