Passports & ID
In the EU all owners need to have a passport for all horses that they own. Any foals or adult horses must be identified with a microchip before passport applications can be made for them.
In the EU foals must have a microchip and passport by 31 December in the year in which they are born. And horses should not move without their passports except in specially defined situations.
The FEI requirements for Identification can be found here