Cal. Rev. & Tax. Code § 6366.5

There are exempted from the taxes imposed by this part the gross receipts from the sale of, and the storage, use, or other consumption in this state of, endangered or threatened animal or plant species, as defined in subdivision (b) of Section 6010.50 if both the seller and the purchaser are nonprofit zoological societies as defined in subdivision (c) of Section 6010.50.