CA Health & Safety Code Section 127585

(a)

Carriers shall accept, and providers shall use, a completed California uniform billing form, or the electronic equivalent, for each instance when a carrier provides coverage for professional health care services and for each instance when a carrier provides coverage for institutional provider services.

(b)

Carriers that are health care service plans licensed under the Knox-Keene Health Care Service Plan Act of 1975 (Chapter 2.2 (commencing with Section 1340) of Division 2 of the Health and Safety Code), and providers of professional health care services or institutional provider services covered by those plans shall be exempt from the requirement of subdivision (a) except in instances when the provider of the professional health care services bills the plan for the specific services provided and in instances when the provider of the institutional provider services bills the plan for the specific services provided.

(c)

Nothing in the forms shall be construed to prohibit a carrier from requiring that its insured or enrollee, or a person acting on behalf of the insured or enrollee, submit other information to the carrier as necessary to determine that the professional health care services or institutional provider services are covered under the terms of the carrier’s health benefits plan.