California Code, Corporations Code - CORP § 10810

(a) At least one-fourth of all licentiates of the particular profession residing in California become members.

(b) Membership in the corporation and an opportunity to render professional services upon a uniform basis are available to all licensed members of the particular profession.

(c) Voting by proxy and cumulative voting are prohibited.

(d) A certificate is issued to the corporation by the particular professional board whose licentiates have become members, finding compliance with the requirements of subdivisions (a), (b), and (c).

Any such corporation shall be subject to supervision by the particular professional board under which its members are licensed and shall also be subject to the part under which it is formed, either Part 2 (commencing with Section 5110) or Part 3 (commencing with Section 7110) of this division, except as to matters specifically otherwise provided for in this article.