Horse and Pony Identification numbers

As detailed in the EA National Dressage Rules, section 4.8.5:

Horse and Pony Identification numbers are compulsory for identification purposes and must be used at all times at an event so that the horse and pony can be identified by all Officials including Stewards.
a) two numbers are required to be worn when competing – one on each side of the horse - preferably attached to both sides of the saddlecloth, or both sides of the bridle and must be clearly legible by the judge/s being a minimum of 3.5 - 4cm in height.
b) the Horse or Pony Identification Number must also be worn as described whenever the horse is being ridden/lunged/led/tethered or grazed from the time of their arrival on the grounds until the end of the event
c) identification numbers shall be in black or dark coloured text, clearly displayed on a white background.

EA Official Competitive Competition - Rider Division/Category

When entering EA Official Competitive classes, the rider must select whether they are riding as Professional (Open),  AOR (Amateur Owner Rider), Pony or Youth. For more detail, please see the Equestrian Australia Dressage rules, available at: https://www.equestrian.org.au/dressage-rules

For reference, the folowing extract from the EA National Dressage Rules is provided:

AOR

Criteria Amateur Owner Rider (AOR) is a division of Official Competitive riders. The intent of the division is to highlight and reward non-professional riders. For the purposes of this rule, a professional is someone who derives an income from activities in equestrian sport including breaking, training, coaching or riding horses. It does not however exclude riders who may also earn a living running an agistment property, work in the racing industry or saddlery for example. It is more about recognising riders with their own horses only to ride and train who are obliged to earn an income to support their sport outside of riding and training.

All amateur owner riders must meet the following criteria:
a) the rider must be a Competitive member of their state branch of Equestrian Australia
b) the horse must have a life registration with Equestrian Australia
c) the horse/pony registration lodged with Equestrian Australia must reflect the name of the amateur owner rider as owner or part-owner of the horse. Leased horses are eligible if the amateur owner rider competitor is reflected as the lessee on the EA horse registration of that horse
d) the rider may not receive payment for activities in equestrian sport including breaking, training, coaching and riding horses
e) the rider’s income may only include sponsorship
f) the horse/pony must be primarily ridden and trained by the rider/owner with only periodic ridden assistance by person(s) other than the owner. This specifically includes the period 4 weeks up to and including the event
g) the rider must be aged 21 and over – can enter in the calendar year in which they turn 21
h) the division is for Official Competitive competitions. The Organising Committees may run this division at any level (ideally at all levels Preliminary - GP) and it can be run either within the competition or separately
i) Organising Committees must designate the AOR on the draw if there is a separate competition conducted within the one competition
j) for a State/Regional/Club Leader Board it would be ideal to select several events at which scores will count towards the annual Leader Board
k) if the OC receives evidence that the rider is in breach of these rules then this rider will forfeit any awards and prizes