California Code, Revenue and Taxation Code - RTC § 5721

For the 1973 calendar year and each calendar year thereafter, on the privilege of breeding, training, caring for or racing a racehorse in this state, there is hereby imposed an annual tax on owners of racehorses for such racehorses domiciled in this state, which shall be in lieu of any property tax on racehorses subject to taxation pursuant to this part.