If you supervise a physician assistant or nurse practitioner in California, the supervising physician requirements in California come down to six things: hold an unrestricted MBC or OMBC license, stay within the statutory caps on how many mid-level providers you oversee, put the right written agreement or standardized procedures in place, remain available for consultation, document your oversight, and accept that responsibility for the care your supervisee delivers runs back to you. The rules differ meaningfully between PAs and NPs, and the compliance failures that draw Board attention are almost always in the details.
Who Can Supervise
You need a current, active license from the Medical Board of California (MBC) or the Osteopathic Medical Board of California (OMBC), with no restrictions that prohibit supervising other practitioners. There is no separate application or Board approval for taking on a PA; the license itself is your authorization as long as it carries no limiting conditions.1Medical Board of California. Supervising Physician Assistants – FAQs
Probation changes the picture. The MBC routinely imposes a standard probation condition prohibiting supervision of PAs and advanced practice nurses. Even without an outright prohibition, any restriction that narrows your own scope of practice narrows what your PA or NP can do, because a supervisee cannot practice beyond what the supervising physician is authorized to perform.
Competency in the relevant clinical area is also expected. A supervising physician needs the training and experience to evaluate the decisions the supervisee is making. A cardiologist overseeing a PA who primarily handles dermatology patients is not a supervisory relationship that holds up under scrutiny.
How Many You Can Supervise
Business and Professions Code Section 3516 caps PA supervision at eight PAs per physician at any one time.2California Legislative Information. California Business and Professions Code 3516 The exception sits in BPC Section 3502.5: during a declared state of emergency, the cap can be lifted.
For NPs who furnish medications under BPC Section 2836.1, the cap is four NPs per physician.1Medical Board of California. Supervising Physician Assistants – FAQs A physician who supervises both can oversee up to 12 total: eight PAs and four furnishing NPs.
NPs certified under AB 890 as 103 or 104 NPs practice without standardized procedures and do not count toward the ratio, because they are not under traditional physician supervision. If you supervise the maximum, the practical question is whether you can carry your own patient load while still reviewing charts, taking consultation calls, and remaining meaningfully involved in clinical decisions. Many groups spread the load across several physicians rather than concentrate it in one.
Supervising a Physician Assistant
The Practice Agreement Defines the Scope
Every PA in California must practice under physician supervision. Independent practice is not an option, and the supervising physician bears responsibility for all medical services the PA provides and must follow each patient’s progress.1Medical Board of California. Supervising Physician Assistants – FAQs
A PA’s scope is not set by the license. It is set by the written practice agreement between the PA and the supervising physician. The PA may perform only the medical services described in that agreement, and must have the competency, education, and training to render them. If the agreement is silent on a service, the PA cannot perform it, even if the physician verbally approves.
Where the practice agreement authorizes the PA to furnish or order drugs, BPC Section 3502.1 requires the agreement to spell out which drugs or devices may be furnished, under what circumstances, the extent of physician oversight, and the method for periodic review of the PA’s competence.3California Legislative Information. California Business and Professions Code 3502.1 Boilerplate language is a common compliance failure. An auditor should be able to read the agreement and tell exactly what the PA is authorized to do.
Availability
Supervision does not require you to be in the room. It does require you to be reachable for consultation at all times when the PA is seeing patients, whether in person or by electronic communication. The standard is continuous availability, not continuous physical presence, which reflects the reality that many PAs work at sites where the supervising physician is elsewhere.
A practice agreement may designate the PA as an agent of the supervising physician for certain acts. That designation does not shift responsibility. The physician retains it.
Supervising a Nurse Practitioner
Standardized Procedures
An NP who has not been certified under AB 890 works under standardized procedures: written policies developed collaboratively by nursing, medicine, and administration within the healthcare system where the NP practices.4Board of Registered Nursing. An Explanation of Standardized Procedure Requirements for Nurse Practitioner Practice Standardized procedures are the legal mechanism that lets an NP perform functions that would otherwise be the practice of medicine.
The procedures must include all required elements under Title 16, California Code of Regulations, Section 1474. At minimum, they identify which functions the NP may perform, under what circumstances, and what clinical situations require physician consultation.4Board of Registered Nursing. An Explanation of Standardized Procedure Requirements for Nurse Practitioner Practice Your role as supervising physician is to be available for consultation, participate in developing and updating the procedures, and ensure the NP stays within the authorized scope. Oversight is more protocol-driven than case-by-case, but responsibility for ensuring compliance with the approved treatment guidelines still sits with you.
Where AB 890 Changes Things
AB 890, signed in 2020 and amended by SB 1451 in 2024, created two NP categories, 103 and 104, that practice without standardized procedures.5California Board of Registered Nursing. Assembly Bill 890 A 103 NP practices in a group setting where at least one physician also practices but is not under that physician’s direct supervision. A 104 NP can practice entirely outside a group setting within their national certification’s population focus.
If you work alongside a 103 or 104 NP, you are not their supervising physician in the traditional sense. They are accountable to the Board of Registered Nursing, must inform new patients that they are not physicians, and do not require chart review by you.5California Board of Registered Nursing. Assembly Bill 890 These NPs also do not count against your ratio caps.
Chart Review and Documentation
The records need to show active oversight, not just a signature on file. For PAs, the practice agreement itself must describe the method of periodic review, including peer review of the PA’s clinical performance.3California Legislative Information. California Business and Professions Code 3502.1 California does not set a single statewide percentage of charts you must audit. The practice agreement sets the standard. In practice, many supervising physicians audit at least 5% of records, targeting the cases with the most clinical risk.
Beyond audits, keep the current practice agreement on file, record supervisory evaluations, and complete any co-signatures the agreement requires. Electronic health records are fine, but the records still have to meet California’s medical record retention rules regardless of format.
For NPs under standardized procedures, documentation centers on the written procedures themselves, keeping them current, and recording consultations between the NP and the supervising physician.
Controlled Substances
Controlled substance prescribing adds requirements beyond ordinary drug furnishing. A PA’s practice agreement must specify which Schedule II through V substances the PA may furnish or order. If Schedule II is included, the agreement must go further and identify the specific diagnoses for which the PA may furnish those drugs.3California Legislative Information. California Business and Professions Code 3502.1 A general authorization to prescribe controlled substances is not enough for Schedule II.
At the federal level, both PAs and NPs who prescribe controlled substances need their own DEA registration. The DEA treats them as mid-level practitioners and looks to state licensing boards to determine what schedules each may prescribe.6Diversion Control Division. Registration Q&A A separate DEA registration is required for each location where controlled substances are dispensed.
Under the MATE Act, effective June 2023, any practitioner applying for a new or renewed DEA registration must complete at least eight hours of training on opioid and substance use disorders.7SAMHSA. Training Requirements (MATE Act) Resources This applies to the supervising physician and the supervised practitioner. Hours can be accumulated across trainings.
Remote and Telehealth Supervision
California already allows a supervising physician to be available electronically rather than physically present for PA supervision, which makes remote oversight workable in rural and underserved areas. Controlled substances are the harder question.
The Ryan Haight Act generally requires at least one prior in-person evaluation before a controlled substance is prescribed via telemedicine. COVID-era flexibilities have been extended through December 31, 2026, allowing DEA-registered practitioners to prescribe Schedule II through V substances by telemedicine without a prior in-person visit, provided the encounter uses real-time audio and video and the prescription is for a legitimate medical purpose.8Federal Register. Fourth Temporary Extension of COVID-19 Telemedicine Flexibilities for Prescription of Controlled Medications A permanent framework is under proposed rulemaking, but the temporary extension is the operative rule.
For Medicare purposes, “direct supervision” of auxiliary personnel now includes virtual presence through real-time audio and video for most services. Audio-only does not count.9eCFR. 42 CFR 410.26 – Services and Supplies Incident to a Physician’s Professional Services: Conditions Remote oversight is more practical than it once was, but meaningful clinical involvement is still required.
Medicare Billing and Incident-To
How you supervise directly affects what you can bill. Under Medicare’s incident-to rules, services furnished by auxiliary personnel can be billed under the supervising physician’s provider number at the full physician rate, but only if the physician provides direct supervision, and only the supervising physician may bill Medicare for incident-to services.9eCFR. 42 CFR 410.26 – Services and Supplies Incident to a Physician’s Professional Services: Conditions
Two categories qualify for less stringent oversight. Designated care management services and behavioral health services furnished by auxiliary personnel can be billed under general supervision, meaning the physician directs and controls the service overall but does not need to be present or immediately available.9eCFR. 42 CFR 410.26 – Services and Supplies Incident to a Physician’s Professional Services: Conditions
Split or shared visits, where a physician and an NP or PA both see the same patient in a facility setting, follow different rules. Medicare pays whichever practitioner performs the substantive portion of the visit, defined as either more than half of the total time or a substantive part of the medical decision-making. Office and nursing facility visits cannot be billed as split or shared services.
Liability if Supervision Falls Short
The supervisory relationship creates real malpractice exposure. Because you accept responsibility for all medical services a PA provides, a negligent act or omission by the PA can flow up to you under respondeat superior, the doctrine that holds employers liable for employees acting within their duties.
NP oversight looks less direct, but a physician who approved the standardized procedures or signed the protocols shares potential liability if the protocols were inadequate or if the physician failed to respond when consulted. An NP’s greater clinical autonomy does not insulate the supervising physician from claims that oversight was insufficient.
Insurance follows the same logic. Malpractice carriers typically want to know how many practitioners you supervise, what their scope of practice includes, and whether written agreements are in place. Exceeding the statutory caps or failing to document oversight can give a carrier grounds to challenge coverage when a claim arises, and some carriers charge higher premiums for physicians who supervise at the maximum.
Board Discipline for Non-Compliance
The MBC and OMBC have broad authority to investigate supervision-related complaints and impose discipline. Penalties range from citations and fines to probation conditions prohibiting supervision of PAs or advanced practice nurses. In serious cases, the Board can suspend or revoke the medical license.
The recurring violations are the same short list: exceeding the ratio caps, allowing a PA to perform services outside the practice agreement, failing to be available for consultation, and neglecting chart review obligations. Supervision complaints often surface during malpractice litigation, when opposing counsel starts asking whether the oversight the law requires was actually happening. Civil liability compounds that risk. Criminal exposure is rare but possible where a complete absence of supervision contributed to serious patient injury or death.