California SB 351: How Dental and Med Spa Practices Must Rebuild Their MSO/PC Books for 2026

If your California dental or med spa practice runs on the classic two-entity setup — a physician-owned professional corporation (PC) handling patients and a management company (MSO) handling everything else — the monthly management fee moving between your two sets of books may now be the single riskiest number in your business.

Effective January 1, 2026, California Senate Bill 351 (SB 351) fundamentally tightened the state's corporate practice of medicine and dentistry rules. It restricts how private equity groups, hedge funds, and their management companies can influence medical and dental practices — including yours, even if no investor has ever set foot in your office. And because the law targets exactly the mechanisms that show up in accounting records — management fees, who hires clinicians, who controls billing, who owns the assets — compliance with SB 351 is, to a surprising degree, a bookkeeping project.

Here is what the law changes, and how to rebuild your chart of accounts, funds flow, and monthly close so your books prove compliance instead of undermining it.

What SB 351 Actually Does​

California has always barred unlicensed corporations from practicing medicine — the corporate practice of medicine (CPOM) doctrine. In practice, though, the industry worked around it with the "friendly PC" model: a licensed physician owns the clinical entity on paper, while an investor-backed MSO runs marketing, staffing, billing, leasing, and equipment under a long-term management services agreement (MSA), often taking a percentage of collections as its fee.

SB 351, signed on October 6, 2025, was written specifically to police that workaround. Its core provisions:

• No investor control over clinical matters. Private equity groups and hedge funds involved with a medical or dental practice may not make or influence clinical decisions — diagnosis, treatment, staffing of clinicians, billing and coding practices, supplies, or medical records.
• Banned contract clauses. Management agreements may not give the MSO or its backers control over hiring and firing physicians and dentists, setting clinical staffing levels, dictating billing procedures, or restricting a clinician's ability to compete or practice elsewhere through overbroad non-competes.
• Direct enforcement. The California Attorney General can investigate and seek injunctions and penalties against the investors and management companies themselves — not just the practice.
• Dental is explicitly in scope. The law covers both medical and dental practices, which puts dental support organizations (DSOs) under the same microscope as medical MSOs.

Although the statute never says the words "med spa," physician-owned aesthetic practices operating through MSO structures are squarely covered. If Botox, fillers, lasers, or wellness infusions are delivered through a PC that pays an MSO, SB 351 applies to you.

A companion law expands transaction notice obligations to the state's health care cost watchdog (the Office of Health Care Affordability) for deals involving MSOs and private equity funds — so both your structure and your next transaction may draw scrutiny.

Why Your Books Are Now Evidence​

Here is the uncomfortable part: nearly every SB 351 violation leaves a paper trail in the general ledger.

• A management fee set as a percentage of collections looks like profit-sharing with unlicensed owners — the classic fee-splitting red flag.
• Clinician payroll running through the MSO's books suggests the management company, not the physician owner, is the real employer.
• Patient revenue landing in the MSO's bank account first suggests the MSO, not the PC, is really practicing medicine.
• Practice equipment and leaseholds titled to the MSO suggest the investors own the practice in everything but name.

Regulators do not need to sit in your exam rooms to build a case. They can read your trial balance. California's Attorney General has already signaled exactly this approach in a settlement with a national dental support organization that drew bright lines around revenue-based management fees, MSO ownership of practice property, and clinician non-compete provisions. Treat that settlement as a preview of the enforcement playbook: every one of those issues is visible in the books.

The flip side is encouraging. Clean, well-separated books with a defensible flat management fee are your best affirmative proof that the physician owner actually controls the practice. Compliance is not just about re-papering contracts — it is about making the money move the way the compliant contracts say it does.

The Compliant Money Model: Two Entities, Two Ledgers, One Arm's-Length Fee​

A compliant MSO/PC structure has a simple financial shape:

1. All patient revenue lands in the PC. Collections from patients and insurers are deposited into bank accounts owned by the professional corporation — never directly into the MSO.
2. The MSO bills the PC a flat, fair-market-value fee. The management fee reflects the actual value of administrative services rendered (rent, staff, marketing, billing support, software), supported by a valuation — not a percentage of revenue, patient volume, or collections.
3. Each entity keeps its own complete books. The PC records the management fee as an operating expense, payable to the MSO. The MSO records the same fee as service income, receivable from the PC. Every dollar is invoiced, recorded on both sides, and reconciled — never handled as an informal transfer or sweep.
4. Clinical costs live in the PC; administrative costs live in the MSO. Clinician compensation, malpractice coverage, and clinical supplies sit on the PC's profit and loss. Marketing, front-desk labor, rent, and practice-management software sit on the MSO's — then get recovered through the fee.

If your current setup has the MSO sweeping a share of daily deposits, booking the fee only on one side, or running clinician payroll, that is the gap SB 351 turns from sloppy into dangerous.

Rebuild Checklist: Seven Bookkeeping Fixes to Make Now​

1. Split (or re-split) your chart of accounts​

Each entity needs its own chart of accounts, its own bank accounts, and its own close. Common contamination to clean up:

• Patient collections deposited to MSO accounts — reroute to the PC.
• MSO operating expenses paid from PC accounts (or vice versa) without intercompany invoicing — stop the commingling and book proper intercompany receivables and payables.
• A single bookkeeper running one combined QuickBooks file for "the practice" — separate the files and the bank feeds.

2. Re-paper the management fee at fair market value​

This is the highest-value fix. Engage a valuation professional to support a flat monthly (or per-service) fee based on the fair market value of the administrative services actually provided, and amend the MSA to match. Then make the accounting follow the paper:

• The MSO issues a real monthly invoice to the PC.
• The PC books management-fee expense; the MSO books management-fee income.
• Reconcile the intercompany balance to zero (net of timing) every month-end. A perpetually growing intercompany balance that nobody reconciles reads like a disguised profit distribution.

Avoid any fee formula tied to a percentage of collections, net income, or patient volume — and avoid mid-year "true-ups" that effectively convert a flat fee back into a percentage.

3. Put clinician employment where it belongs​

Physicians, dentists, nurse injectors, and hygienists who exercise clinical judgment should be employed (or contracted) by the PC — with offer letters, payroll records, credentialing files, and malpractice coverage to prove it. If your MSO currently hires, fires, disciplines, or sets productivity quotas for clinicians, both the contracts and the payroll postings need to move. At minimum, the MSO should never be the entity signing a clinician's employment agreement.

4. Title assets and leases consistently with the story​

Review who owns the chairs, lasers, imaging equipment, and who holds the office lease. Where the MSO owns assets the PC uses, document it as a straight equipment lease or sublease at fair market rent — with invoices and payments, not handshake arrangements. An MSO that owns everything, employs everyone, and takes a cut of everything is, economically, the practice. Your fixed-asset register should not tell that story.

5. Scrub banned clauses from every agreement — then mirror the cleanup in the ledger​

Non-competes binding clinicians to the MSO, MSO approval rights over clinical hiring, MSO control of billing and coding, and MSO access to or ownership of medical records are all in the law's crosshairs. As counsel amends the MSA, update the operations the ledger records: who approves write-offs, who owns the billing NPI enrollments, who pays the coding staff. If the amended contract says the PC controls billing but the MSO's employees still submit every claim with no PC oversight, the books will contradict the contract.

6. Build a monthly compliance close​

Add standing month-end procedures that double as an evidence file:

• Intercompany reconciliation signed off by both entities.
• Management-fee invoice matched to the MSA rate schedule, with any variance explained in writing.
• Separate P&Ls reviewed by the physician owner, with minutes or written acknowledgment showing the owner reviewed practice finances and clinical staffing decisions.
• A log of clinical decisions (hiring, protocols, billing policy changes) documenting physician approval.

Keep policies, meeting minutes, and attestations showing clinical decisions remain under physician control. If the Attorney General ever asks, this file is your first exhibit.

7. Prepare for transaction scrutiny before you need it​

If you plan to sell, recapitalize, bring in a partner, or expand into California, assume the deal will be reviewed. Buyers and their lenders now discount practices with percentage-based fees and commingled books — or walk away entirely. A year of clean, separated financials with a supported flat fee is a valuation asset. Start the clock now.

Mistakes That Turn an Audit Into a Case​

Watch for these patterns, each of which converts ordinary messiness into an SB 351 exhibit:

• The percentage fee nobody renegotiated. Pre-2025 MSO agreements overwhelmingly used revenue-based fees. If yours still does, the amendment cannot wait.
• The fee booked as a transfer. Moving money between entities with no invoice, no expense posting on the PC side, and no income posting on the MSO side looks like skimming, even when it is just laziness.
• The MSO-employed medical director. A medical director on the MSO's payroll, supervising clinicians employed by someone else, inverts the required control relationship.
• The unreconciled intercompany account. A balance that grows for quarters without settlement suggests the entities are not really separate.
• Copy-paste MSAs from another state. Management agreements drafted for Texas or Florida often contain control provisions California now bans outright. Every template needs California-specific review.

What If You Operate Outside California?​

Pay attention anyway. California has a long history of exporting its health care regulations, and similar scrutiny of investor-backed practices is already building in New York, Massachusetts, Illinois, and Washington. Even where no SB 351 equivalent exists yet, the underlying principles — fair-market-value fees, no fee-splitting, physician control of clinical decisions — already exist in most states' laws. Building compliant books now is portable insurance: the same separated ledgers and flat-fee documentation that satisfy Sacramento will satisfy any state that follows.

Lenders are also national. Practice-acquisition underwriting increasingly asks for MSO/PC separation, fee studies, and intercompany reconciliations regardless of the state on the letterhead.

Keep Your Practice's Finances Organized From Day One​

Restructuring for SB 351 means running two clean sets of books, reconciling intercompany balances monthly, and keeping a paper trail that proves physician control — exactly the kind of transparent, auditable financial record-keeping that plain-text accounting was designed for. Beancount.io gives you version-controlled, fully transparent books with no black boxes, so every management-fee invoice, intercompany reconciliation, and month-end review is traceable. Get started for free and bring proof-ready order to your practice's finances.