PDFWAC 260-28-100
Change of trainers.
(1) If an owner changes trainers, he/she must notify the racing commission within seventy-two hours. This form must be signed by the new trainer acknowledging that he/she accepts responsibility for the horse or horses, and by the previous trainer to release any obligations in connection with the horse or horses.
(2) Following a transfer of trainers, the horse may not be transferred back to the original trainer for a minimum of thirty days without approval of the board of stewards.