California Code, Health and Safety Code - HSC § 1366.4

(a) A medical group, physician, or independent practice association that contracts with a health care service plan may enter into contracts with licensed nonphysician providers to provide services, as defined in Section 1300.67(a)(1) of Title 28 of the California Code of Regulations, to plan enrollees covered by the contract between the plan and the group, physician, or association.

(b) The licensed nonphysician provider described in subdivision (a) that contracts with a medical group, physician, or independent practice association may directly bill, if direct billing is otherwise permitted by law, a health care service plan for covered services pursuant to a contract with the health care service plan that specifies direct billing. Direct billing pursuant to this subdivision is permitted only to the extent that the same services are not billed for by the medical group, physician, or independent practice association.

(c) A health care service plan may require the nonphysician provider to complete an appropriate credentialing process.

(d) Every health care service plan may either list licensed nonphysician providers that contract with medical groups, physicians, and independent practice associations pursuant to subdivision (b) in any listing or directory of plan health care providers that is provided to enrollees or to the public, or may include a notification in the plan's evidence of coverage or provider list that the health care service plan has contracts with nonphysician providers, pursuant to subdivision (b), and may list the types of contracted nonphysician providers. The notification may inform an enrollee that he or she may obtain a list of the nonphysician providers by contacting his or her primary or specialist medical group. The listing may indicate whether licensed nonphysician providers may be accessed directly by enrollees.

(e) Nothing in this section shall be construed to authorize, or otherwise require the director to approve, a risk-sharing arrangement between a plan and a provider.