Okla. Admin. Code § 325:35-1-35
Any agreement, covenant, or contract entered into by the duly elected Horsemen's Organization with any Organization Licensee is binding upon each horse Owner or Trainer or participant who accepts the conditions of the race meeting by entering a horse at such race meeting, except a participant may sign a waiver electing to be excluded from any purse dedication, prize or other monies which are the subject of the agreement between the Horsemen's Representative and the racetrack. No such Owner or Trainer or participant nor any member, employee, agent, director, or representative of a Horsemen's Organization shall counsel, urge, advocate, aid, or abet the violation of any provision of any horsemen's agreement with any Organization Licensee during its term.
Okla. Admin. Code § 325:35-1-35