"It is absolutely necessary for the Jack Stock to have their own registry for them to get the recognition in the show ring and the world market. We have been running the risk for a long time of becoming a large donkey."
- Gail Flach, Coffee Hollow Jackstock, 2003
Mammoth Jack Stock jacks, jennets and geldings meeting the criteria outlined in the Rules of Entry are eligible to be entered in the AMJR Stud Book. Animals registered before maturity, are issued a certificate that includes no measurements, and is considered to be a temporary registry entry. A registry update is required to be submitted when the animal reaches maturity (typically at five years of age). Upon receipt of the update, and verification by the AMJR Registrar that the animal meets the registry requirements, a permanent certificate of registry is issued.