US Jockey Club Rule Changes to Restrict Stallion Books

Media Release - Friday May 8

The Jockey Club board of stewards has announced that it has adopted a final rule limiting the annual breeding of individual stallions. The rule reflects The Jockey Club’s goal to preserve the health of the Thoroughbred breed for the long term and will apply prospectively to stallions born in 2020 or later. 

Effective today, The Jockey Club’s Principal Rules and Requirements of the American Studbook are amended by adding the following italicized language to the text of Rule 14C:

C. Based on the information on a completed Report of Mares Bred form, The Jockey Club will forward to the stallion owner, lessee or authorized agent a preprinted Service Certificate for each broodmare bred, including the name of the stallion, the name of the broodmare, the name of the dam of the broodmare, and the date of the last cover.

The total number of broodmares bred per individual stallion whose year of birth is 2020 or thereafter shall not exceed 140 per calendar year in the United States, Canada, and Puerto Rico. The Jockey Club shall limit the number of Stallion Service Certificates for such stallions to a maximum of 140 per calendar year.

When the stallion owner, lessee or authorized agent receives the preprinted Service Certificate, it should be examined for accuracy, signed by the stallion owner, lessee or authorized agent and forwarded to the breeder of the foal or submitted to The Jockey Club through Interactive Registration™ at www.registry.jockeyclub.com. The Service Certificate is required to register a foal. Service Certificates will not be issued unless a completed Report of Mares Bred form is on file at The Jockey Club and until genetic or re-DNA typing of the stallion has been completed (see Rule 5).

In an effort to illustrate the operation of the new rule, The Jockey Club offers the following examples of how it will be applied:

(1)  For stallions born in 2019 and earlier, there will be no limit to the number of mares reported bred in the United States, Canada, and Puerto Rico. The Jockey Club will issue stallion certificates for all mares bred by such stallions within the United States, Canada, and Puerto Rico during a calendar year.

(2)  For stallions born in 2020 and later, the maximum number of mares covered within the United States, Canada, and Puerto Rico in a calendar year will be 140. It would be a violation of Rule 14C for such a stallion to cover more than 140 mares within the United States, Canada, and Puerto Rico during a calendar year. The aforementioned limit will apply to all mares bred during a calendar year regardless of when The Jockey Club receives a Report of Mares bred (or any amendments or supplements thereto).

The Jockey Club will modify its Report of Mares Bred form and other related forms in recognition of the amendment to Rule 14. Stallion Service Certificates will be issued on the basis of first cover date in the order of mares listed on the Report of Mares Bred.

The Jockey Club is grateful for the many thoughtful comments in response to its September rule proposal. The stewards carefully considered those comments in formulating a rule that will promote diversity of the Thoroughbred gene pool and protect the long-term health of the breed. 

The Jockey Club will continue to maintain the Principal Rules and Requirements of the American Studbook in keeping with its mission to ensure the health of the Thoroughbred breed.

The Jockey Club, founded in 1894 and dedicated to the improvement of Thoroughbred breeding and racing, is the breed registry for North American Thoroughbreds. In fulfillment of its mission, The Jockey Club, directly or through subsidiaries, provides support and leadership on a wide range of important industry initiatives, and it serves the information and technology needs of owners, breeders, media, fans and farms. It is the sole funding source for America’s Best Racing, the broad-based fan development initiative for Thoroughbred racing.

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