The Alcohol and Gaming Commission of Ontario's expansion of claiming rules in the Standardbred Rules of Racing is now in effect.

These changes, previously announced in detail on Nov. 12, 2025, expand the criteria for claims to be invalidated in certain circumstances after a claiming race and add a requirement for a pre-race warm-up assessment and post-race Observation Period.

Minor procedural changes to claiming rules in the Thoroughbred Rules of Racing are also now in effect.

The AGCO stated that expanding the invalidation of claims rules is part of a continued effort to help ensure the highest standards of health, safety and accountability across the horse racing industry in Ontario, aligning with the AGCO’s commitment to fostering sustainability in the sectors it regulates.

The changes go into effect on Feb. 2, 2026. 

Click here to download an AGCO Standardbred Official Claim Form, which is the only form that will be accepted by Judges, effective Feb. 2, 2026. Claims will not be accepted if a telephone number for the new trainer is not provided.

Summary of Standardbred changes

• Prior to racing, horses are required to complete a mandatory one-lap warm-up observed by an Official or Commission Veterinarian to assess their movement and condition on the racing surface.
• Horses are now automatically opted into a post-race observation, which provides more opportunity for any issues that would place a horse on the Veterinarians’ List to become visible. The Observation Period is to take place a minimum of 30 minutes after a claiming race.
• Claimants can choose to opt out of the Observation Period directly on the claim slip; however, doing so forfeits the enhanced invalidation of claims protections.
• The original trainer (or their representative) must take the horse directly to the observation area following a claiming race (or once they are excused from the test barn, if selected for testing) and stay for the duration of the Observation Period. Failure to comply may result in monetary penalties.
• If before the end of the Observation Period the Official or Commission Veterinarian places a horse on the Veterinarian’s List, or the horse is seen bleeding from the nostrils, requires euthanasia due to an injury, or dies, the claimant will have the option to ask the Race Officials to invalidate the claim.
• If the claimant opts to have a claim invalidated by a Race Official, the horse is to be returned to the original owner in the same physical and medical condition as when it was claimed.  

Summary of Thoroughbred changes

• Horses will now be automatically opted into the Observation Period, to take place a minimum of 30 minutes after a claiming race.
• Claimants can choose to opt out of the Observation Period directly on the claim slip; however, doing so forfeits the enhanced invalidation of claims protections.

For any questions regarding changes to the claiming rule expansions, see the AGCO's Race Day Contact List.

(With files from AGCO)