California Code, Business and Professions Code - BPC § 25503.3

(a) Notwithstanding any other provision of this division, any winegrower, beer manufacturer, brandy manufacturer, distilled spirits manufacturer, craft distiller, or distilled spirits manufacturer's agent may, at parties held, or in hospitality rooms maintained, in conjunction with meetings, conventions, or combined conventions and trade shows of bona fide trade associations of retail licensees, serve and provide free of charge, food, alcoholic and nonalcoholic beverages, entertainment, and recreational activities to the retail licensees and their guests while attending those meetings, conventions, or combined conventions and trade shows.  Additionally, any person specified in this section may pay a fee to the bona fide trade association for the privilege of providing food, alcoholic or nonalcoholic beverages, entertainment, or recreational activities, or for display booth space, as long as the fee is at the same rate charged all suppliers.

(b) Any person specified in subdivision (a) may advertise in any regular publication of a bona fide trade association the members of which are food or alcoholic beverage retailers, if that publication does not advertise on behalf of, or directly benefit, any individual retail licensee.  The advertising fee paid to the bona fide trade association or its agent shall be at the same rate charged all advertisers.

(c) Any person specified in subdivision (a) may pay membership dues to a bona fide trade association as long as the dues are at the same rate charged all nonretail members of the association.

(d) A licensed beer manufacturer or a brewpub-restaurant licensee may serve, for consumption on the premises, beer produced by the licensed beer manufacturer or brewpub-restaurant licensee to attendees at a meeting of a bona fide beer manufacturer trade association or brewers' guild held on the premises of a licensed beer manufacturer.