Both, in most cases. The medical director is the practice’s physician of record under California’s Medical Practice Act. The collaborating physician is the named supervising physician for each NP or PA under §2836.1 and §3516. A practice with NPs or PAs on staff requires a medical director at the practice level and a collaborating physician for each NP and PA. However, one physician can fill both roles if the documentation substantively separates them. Practices with no NPs or PAs need only the medical director. The medical director vs collaborating physician treatment covers the role distinction at the framework level.

Not directly. California’s CPOM bar at §2400 prohibits non-physician ownership of the medical practice. Non-physician founders participate through an MSO that contracts with the Professional Corporation. The PC owns the clinical activity and is owned by a physician or is majority-owned by physicians, with up to 49% held by certain licensed allied professionals. The MSO holds the brand, marketing, real estate, and operational functions. Medical revenue flows through PC-controlled accounts.

Under Moscone-Knox, certain licensed allied professionals can hold up to 49% of a Medical Corporation’s shares. California-licensed physicians must hold the remaining 51%. NPs are among the allied professionals eligible for shareholder participation. Non-licensed founders cannot hold any direct interest in the Medical Corporation. MedSpire Health recommmends that California practices use the MSO-PC structure even when an NP could hold shares directly, because the MSO-PC is easier to restructure when a physician shareholder departs.

Yes, for many functions, but California’s substantive engagement standard still applies. Remote medical directors can examine charts, author standing orders, approve protocols, and remain accessible to clinical staff. The substantive engagement standard requires actual engagement, not a nominal name on paperwork. Site visits are not categorically required, but periodic in-person presence supports the substantive engagement standard when MBC inquiries arise. Practices structuring remote engagements document the supervision protocol in substantive detail.

A Good Faith Exam is the pre-treatment medical evaluation that must be performed by a qualifying practitioner (physician, NP, or PA in California) before any prescription medical-aesthetics service. The GFE can be synchronous (real-time, in person or by telehealth) or asynchronous (store-and-forward, subject to time-window constraints). The medical director typically authors the GFE protocol that the qualifying practitioner follows. RNs cannot perform GFE for patients they will treat.

SB 351 (effective January 1, 2026) authorizes the California Attorney General to enforce CPOM directly against PE- and hedge-fund-affiliated medical practices. AB 1415 (effective January 1, 2026) expands the Office of Health Care Affordability’s pre-transaction notice obligations to broader categories of medical practice transactions. Practices with institutional capital face both layers. Practices without institutional capital face SB 351 indirectly through enforcement posture but no new filing obligations under AB 1415.

Under §2836.1. A physician can supervise at most four NPs under standardized procedures. Under §3516 (as amended by AB 1501), a physician can supervise up to eight PAs as of January 1, 2026, up from four previously. NPs operating under the AB 890 §103 transitional pathway or §104 independent pathway do not count against the 4-NP cap and do not require a named collaborating physician of record.

Start with the trio diagnostic. If your practice is in pre-launch planning, the CPOM and MSO-PC structure decision comes first because it shapes every other decision. If your practice is in active operation without a current concern, the medical director engagement audit is the highest-yield starting point. If your practice has NPs or PAs on staff and you are growing, the collaborating physician cap analysis is the binding constraint to plan around.