Cal. Bus. & Prof. Code § 654.2

(a) It is unlawful for any person licensed under this division or under any initiative act referred to in this division to charge, bill, or otherwise solicit payment from a patient on behalf of, or refer a patient to, an organization in which the licensee, or the licensee’s immediate family, has a significant beneficial interest, unless the licensee first discloses in writing to the patient, that there is such an interest and advises the patient that the patient may choose any organization for the purpose of obtaining the services ordered or requested by the licensee.
(b) The disclosure requirements of subdivision (a) may be met by posting a conspicuous sign in an area which is likely to be seen by all patients who use the facility or by providing those patients with a written disclosure statement. Where referrals, billings, or other solicitations are between licensees who contract with multispecialty clinics pursuant to subdivision (l) of Section 1206 of the Health and Safety Code or who conduct their practice as members of the same professional corporation or partnership, and the services are rendered on the same physical premises, or under the same professional corporation or partnership name, the requirements of subdivision (a) may be met by posting a conspicuous disclosure statement at a single location which is a common area or registration area or by providing those patients with a written disclosure statement.
(c) On and after July 1, 1987, persons licensed under this division or under any initiative act referred to in this division shall disclose in writing to any third-party payer for the patient, when requested by the payer, organizations in which the licensee, or any member of the licensee’s immediate family, has a significant beneficial interest and to which patients are referred. The third-party payer shall not request this information from the provider more than once a year.
Nothing in this section shall be construed to serve as the sole basis for the denial or delay of payment of claims by third party payers.
(d) For the purposes of this section, the following terms have the following meanings:
1. (1) “Immediate family” includes the spouse and children of the licensee, the parents of the licensee and licensee’s spouse, and the spouses of the children of the licensee.
2. (2) “Significant beneficial interest” means any financial interest that is equal to or greater than the lesser of the following:
  1. (A) Five percent of the whole.
  2. (B) Five thousand dollars ($5,000).
3. (3) A third-party payer includes any health care service plan, self-insured employee welfare benefit plan, disability insurer, nonprofit hospital service plan, or private group or indemnification insurance program.
  A third party payer does not include a prepaid capitated plan licensed under the Knox-Keene Health Care Service Plan Act of 1975 or Chapter 11a (commencing with Section 11491) of Part 2 of Division 2 of the Insurance Code.
(e) This section shall not apply to a “significant beneficial interest” which is limited to ownership of a building where the space is leased to the organization at the prevailing rate under a straight lease agreement or to any interest held in publicly traded stocks.
(f)
1. (1) This section does not prohibit the acceptance of evaluation specimens for proficiency testing or referral of specimens or assignment from one clinical laboratory to another clinical laboratory, either licensed or exempt under this chapter, if the report indicates clearly the name of the laboratory performing the test.
2. (2) This section shall not apply to relationships governed by other provisions of this article nor is this section to be construed as permitting relationships or interests that are prohibited by existing law on the effective date of this section.
3. (3) The disclosure requirements of this section shall not be required to be given to any patient, customer, or his or her representative, if the licensee, organization, or entity is providing or arranging for health care services pursuant to a prepaid capitated contract with the State Department of Health Services.