California Code, Business and Professions Code - BPC § 25503.28

(a) Notwithstanding any other provision of this division, the holder of no more than six on-sale licenses, or any officer, director, employee, or agent of that licensee, may own a licensed beer manufacturer holding a license pursuant to Section 23357, and may serve on the board of directors and as an officer or employee of a licensed beer manufacturer.  A beer manufacturer, regardless of how many beer manufacturer licenses are held by the beer manufacturer alone, under common ownership with any other licensed beer manufacturer, or under common ownership with any officer, director, employee, or agent of that beer manufacturer licensee who is operating as an on-sale retailer pursuant to this section, shall be prohibited from exercising alone or in common any combination of retail privileges authorized under this section and subdivision (c) of Section 23389 that would result in that beer manufacturer exercising retail privileges at more than eight locations, provided that, subject to the limitations of this section, no more than six of which may be on-sale licenses.  This section shall not limit the number of licensed beer manufacturer locations or the exercise of retail privileges at those licensed beer manufacturer locations as authorized pursuant to Section 23357.

(b) An on-sale licensee specified in subdivision (a) shall purchase no alcoholic beverages for sale in this state other than from a wholesale or winegrower licensee, except for any alcoholic beverages manufactured by the licensed beer manufacturer whose premises of production are located no more than five miles from the licensed on-sale premises.

(c) The Legislature finds that it is necessary and proper to require a separation between manufacturing interests, wholesale interests, and retail interests in the production and distribution of alcoholic beverages in order to prevent suppliers from dominating local markets through vertical integration and to prevent excessive sales of alcoholic beverages produced by overly aggressive marketing techniques.  The Legislature further finds that the exception established by this section to the general prohibition against tied interests must be limited to its expressed terms so as not to undermine the general prohibition, and intends that this section be construed accordingly.