It is essential that an explanation be provided about IAP horses. These horses lack any verified genealogy, and that were registered so that their offspring could be registered, without the guarantee that these IAP horses were really PRE horses. Several years ago, and for a limited period of time, these horses could register their descendents. This was the acceptable practice for some time, until the (Cria Caballar) stud book was closed in Australia, as of which date, these exceptions were no longer accepted. In some cases, these IAP horses were graded (evaluated). If they were considered ""approved"" from that point onwards, these horses were considered PRE in all aspects. If documents (a copy of the basic aptitude certificate) are provided showing that the IAP horse was later graded (evaluated) by Cria Caballar, approved and a blood determination was performed, then the said horse is authorized to have offspring registered as a PRE, the same as any other normal registration. On the other hand, those IAP horses that fail to provide proof that they were graded (evaluated) as PRE horses are not authorized to have offspring registered as PRE horses.