California Code, Revenue and Taxation Code - RTC § 201.2

(a) A nonprofit corporation which has contracted with the board of supervisors pursuant to Section 25905, 25906, 25907, or 25908 of the Government Code for the conduct of an agricultural fair, shall be deemed to be an agency of the county for purposes of this part and for no other purpose, and county-owned property, including possessory interests in that property, used or possessed by the nonprofit corporation in the conduct of an agricultural fair shall be exempt from taxation under subdivision (b) of Section 3 of Article XIII of the State Constitution.

(b) This section shall not be construed to exempt any profit-making organization or concessionaire from any property tax, including a property tax on a possessory interest, for the use of property which is used by a nonprofit corporation for the conduct of a fair.