Health & Saf. Code, § 1373.10

(a) On and after January 1, 1985, every health care service plan, that is not a health maintenance organization or is not a plan that enters exclusively into specialized health care service plan contracts, as defined by subdivision (n) of Section 1345, which provides coverage for hospital, medical, or surgical expenses, shall offer coverage to group contract holders for expenses incurred as a result of treatment by holders of certificates under Section 4938 of the Business and Professions Code, under such terms and conditions as may be agreed upon between the health care service plan and the group contract holder.

A health care service plan is not required to offer the coverage provided by this section as part of any contract covering employees of a public entity.

(b) For the purposes of this section, “health maintenance organization” or “HMO” means a public or private organization, organized under the laws of this state, which does all of the following:

(1) Provides or otherwise makes available to enrolled participants health care services, including at least the following basic health care services: usual physician services, hospitalization, laboratory, X-ray, emergency and preventive services, and out-of-area coverage.

(2) Is compensated, except for copayments, for the provision of basic health care services listed in paragraph (1) to enrolled participants on a predetermined periodic rate basis.

(3) Provides physician services primarily directly through physicians who are either employees or partners of the organization, or through arrangements with individual physicians or one or more groups of physicians, organized on a group practice or individual practice basis.