Cal. Ins. Code § 10133.12

(a) Commencing January 1, 2027, or when final federal rules are implemented, whichever occurs later, the department shall require a health insurer to establish and maintain the following application programming interfaces (API) for the benefit of all insureds and contracted providers, as applicable:
1. (1) Patient access API.
2. (2) Provider access API.
3. (3) Payer-to-payer API.
4. (4) Prior authorization API.
(b) API described in subdivision (a) shall be in accordance with standards published in a final rule issued by the federal Centers for Medicare and Medicaid Services and published in the Federal Register, and shall align with federal effective dates, including enforcement delays and suspensions, issued by the federal Centers for Medicare and Medicaid Services.
(c) Until January 1, 2027, the commissioner may issue guidance to health insurers regarding compliance with this section and that guidance shall not be subject to the Administrative Procedure Act (Chapter 3.5 (commencing with Section 11340) of Part 1 of Division 3 of Title 2 of the Government Code).
(d) This section does not limit existing requirements under this chapter, including, but not limited to, Section 10133.15.