Key Takeaways

• Medicare CHOW under 42 C.F.R. § 489.18 gives a buyer two distinct paths: assume the seller’s provider agreement (no billing gap, inherit exposure) or apply for new enrollment (billing gap during processing, isolated from seller’s exposure). Each has trade-offs.
• Medi-Cal has no uniform CHOW framework. The analysis depends on the target’s specific Medi-Cal enrollment (fee-for-service vs. managed care) and any managed-care contracts.
• Commercial payors typically require consent or novation on assignment of the provider participation agreement. Some payors treat CHOW as a termination event requiring the buyer to apply as a new provider.
• The CHOW analysis is a distinct due-diligence line that runs in parallel with the CPOM structural diligence. Buyers focused on structural remediation sometimes underestimate the payor-transition complexity.
• For predominantly cash-pay targets, the payor-transition analysis simplifies to superbill practices, HSA/FSA acceptance, and any residual payor arrangements. The full CHOW framework is not triggered.

Medicare CHOW and Payor Re-Enrollment for California Treatment Business Acquisitions

For most non-licensee acquisitions of California treatment businesses in the med spa, IV, hyperbaric, wellness, and mental-health-adjacent segments, the payor-transition analysis is limited — the targets are predominantly cash-pay and the Medicare Change of Ownership mechanics don’t apply. For targets with meaningful payor participation (medical HBOT with wound-care programs, ketamine practices with Spravato-adjacent commercial payor billing, TRT platforms with commercial insurance, Medicare-enrolled practices generally), the CHOW analysis under 42 C.F.R. § 489.18 becomes a load-bearing part of the deal structure. It affects closing timing, billing continuity, historical-exposure inheritance, and the buyer’s day-one operational posture.

This post walks through the CHOW framework, the buyer’s two paths (assumed provider agreement vs. new enrollment), and the Medi-Cal and commercial payor considerations that run alongside. It sits under the buyer pillar for the CPOM Acquisition & Remediation cluster.

When CHOW Actually Applies

Not every treatment-business acquisition triggers a Medicare CHOW. The threshold question is whether the seller holds a Medicare provider agreement — that is, whether the seller is enrolled with Medicare and bills Medicare for services under a Medicare provider number.

For California treatment businesses in the segments this cluster addresses, Medicare enrollment is uncommon at retail scale. Cash-pay med spas, mobile IV clinics, wellness hyperbaric centers, ketamine practices marketed for mental-health indications, GLP-1 weight-loss clinics, and cash-pay TRT platforms typically operate outside Medicare. Where Medicare enrollment does exist:

• Medical HBOT practices integrated with wound-care programs, hospital outpatient departments, or academic medical centers bill Medicare for FDA-cleared indications under CPT code 99183.
• Ketamine practices offering FDA-approved Spravato (esketamine) for treatment-resistant depression bill Medicare Advantage and commercial payors under the REMS-restricted delivery framework.
• Multi-specialty practices that combine wellness-oriented services with insurance-billed primary or specialty care.
• Practices that acquired Medicare enrollment during a prior transaction and continue to bill Medicare even where the current service mix is predominantly cash-pay.

Whether a target holds Medicare enrollment is a diligence question the buyer’s counsel should answer early. The answer determines whether the full CHOW analysis applies or whether the payor-transition analysis simplifies.

The Two Paths Under 42 C.F.R. § 489.18

Where Medicare enrollment exists, 42 C.F.R. § 489.18 gives the buyer two distinct paths.

Path 1: Assumed provider agreement. The buyer takes assignment of the seller’s Medicare provider agreement and continues billing under the seller’s Medicare provider number through the transition. Under § 489.18, a change of ownership does not automatically terminate the provider agreement — the buyer can accept the agreement as-is and continue provider participation without a break in billing. What the buyer inherits along with the agreement:

• The seller’s cost-report obligations for periods before the CHOW.
• Potential prior-period overpayment exposure — any Medicare recoupment for services rendered during the seller’s period of participation follows the provider number.
• Any pending audit or investigation.
• The seller’s compliance history and any prior corrective action plans.
• The seller’s payor participation terms (rate schedule, network status, quality reporting requirements).

The advantage is continuity — no billing gap, no patient-flow disruption, no need to file new CMS-855 enrollment forms and wait for approval. The disadvantage is inherited exposure, everything that attached to the seller’s provider agreement follows the buyer.

Path 2: New enrollment. The buyer’s new PC applies for its own Medicare enrollment through the CMS-855A (institutional providers) or CMS-855I (individual providers) or CMS-855B (clinics and group practices) forms depending on the target type. During the enrollment processing period — commonly measured in months rather than weeks — the buyer either operates without Medicare billing (accepting a revenue gap) or bills Medicare only after retroactive enrollment approval (which is possible in specific circumstances but not guaranteed).

The advantage is isolation — the buyer’s new PC starts fresh, without inheriting the seller’s cost-report history, audit exposure, or prior-period recoupment exposure. The disadvantage is timing, for practices with meaningful Medicare revenue, the enrollment processing gap can create material cash-flow disruption.

The buyer’s choice between the two paths depends on the specific facts: the size of the seller’s Medicare revenue relative to the acquisition price; the seller’s compliance history and known exposure; the buyer’s tolerance for a billing gap; and the buyer’s post-closing operational plans. Neither path is categorically better; both are legitimate structures.

The Timing of the CHOW Notice

Regardless of which path the buyer chooses, the CHOW itself has to be reported to Medicare. Under § 489.18(b), notice of a change of ownership must be provided to the CMS Regional Office not later than 45 days after the effective date of the change. Practical practice is to file the CHOW notice before closing or contemporaneously with closing, using CMS Form 855A (for institutional providers) with the appropriate change-of-ownership sections completed.

Late CHOW filing can create provider agreement complications and, in some fact patterns, potential payment recoupment for services rendered during the unnotified period. Timely filing is standard practice.

Medi-Cal — No Uniform CHOW

Medi-Cal (California’s Medicaid program) does not have a uniform CHOW framework analogous to Medicare’s § 489.18. The analysis depends on which Medi-Cal category the target participates in:

Fee-for-service Medi-Cal. Provider enrollment through the Department of Health Care Services (DHCS) generally requires the buyer’s new PC to enroll separately as a Medi-Cal provider. Historical Medi-Cal billing does not transfer to the buyer. This process runs through the Provider Application and Validation for Enrollment (PAVE) system.

Medi-Cal managed care. Where the target participates in Medi-Cal through a managed care plan (typical for most Medi-Cal enrollees in California), the provider agreement is between the target and the managed care plan, not directly with DHCS. Each managed care plan has its own credentialing and change-of-ownership requirements. Some plans allow assignment; some require the new provider to re-credential; some treat CHOW as a termination event.

County Organized Health Systems and Regional Programs. Certain California regions operate managed Medi-Cal through specific county-organized frameworks with their own transition mechanics. Buyer diligence should identify which specific Medi-Cal arrangements the target participates in.

For most non-licensee acquisition targets in the wellness and mental-health-adjacent segments, Medi-Cal participation is limited or absent. Where it exists, the analysis is one of the more complex parts of the payor-transition diligence and warrants specific California healthcare counsel review.

Commercial Payor Transitions

Commercial payor participation agreements are governed by the specific contract between the target and each payor. Common patterns:

Consent required for assignment. Most commercial payor participation agreements require the payor’s written consent for assignment of the agreement to a new provider entity. Assignment without consent typically constitutes a breach and can terminate the participation.

CHOW as termination event. Some payors treat any change of ownership as an event that terminates the existing participation agreement, requiring the buyer to apply as a new provider. The application, credentialing, and negotiation timeline for a new participation agreement can run months.

Novation. In some cases the buyer, seller, and payor execute a three-party novation agreement that transfers the participation agreement to the buyer’s new PC while preserving the rate schedule and network status. Novation is typically preferred by buyers because it preserves continuity, but requires payor cooperation.

Delegated credentialing. Practices that participate through group credentialing arrangements (typical for platforms and multi-location groups) have their own transition mechanics. The buyer’s diligence should surface the specific credentialing arrangements for each payor.

The commercial payor transition planning has to run in parallel with the CPOM structural work and the Medicare CHOW planning. Practices with a meaningful commercial payor mix often find the payor-transition work is a substantial fraction of the total closing timeline.

Superbill Practices

For predominantly cash-pay practices, the payor-transition analysis often simplifies to the superbill question. A superbill is a receipt the practice provides to patients that patients can submit to commercial insurance for out-of-network reimbursement. The superbill represents to the payor that the services were rendered by an authorized provider — which raises a specific compliance question for practices that have been operating through a non-compliant structure.

If the seller has been offering superbills through a non-physician-owned LLC, the superbills have represented that the LLC rendered medical services — which is precisely the CPOM issue the buyer’s diligence should have surfaced. Post-closing, the buyer’s new PC issues superbills that accurately represent the PC as the rendering provider. The historical superbill issue is a diligence line for the buyer to price into the deal.

HSA/FSA acceptance is a related but simpler category — the practice accepts payment from HSA or FSA debit cards for qualifying services. The buyer’s post-closing practice can accept HSA/FSA payments through the standard merchant processor without specific payor enrollment.

When to Bring Counsel Into the Payor-Transition Analysis

Before the LOI is signed. The choice between the assumed-provider-agreement path and the new-enrollment path drives closing timing and every downstream commercial term. For targets with meaningful Medicare, Medi-Cal, or commercial payor participation, the payor-transition diligence should surface the specific arrangements the target holds and identify the timing constraints those arrangements impose on the deal.

Bay Legal, PC represents non-licensee buyers of California treatment businesses through pre-LOI structural counsel, CPOM diligence, payor-transition analysis, and deal documentation. Call (650) 668-8000 or schedule a consultation at baylegal.com/contact.

Frequently Asked Questions

Does every California treatment business acquisition trigger a Medicare CHOW?

No. The Medicare CHOW framework under 42 C.F.R. § 489.18 applies only where the seller holds a Medicare provider agreement. For predominantly cash-pay practices in the med spa, wellness IV, wellness hyperbaric, GLP-1 weight-loss, and cash-pay TRT segments, Medicare enrollment is uncommon and the CHOW analysis does not apply. Where Medicare enrollment exists, the CHOW is a load-bearing part of the deal structure.

What is the difference between assuming the seller’s provider agreement and applying for new Medicare enrollment?

Assuming the seller’s provider agreement means the buyer takes assignment of the existing agreement and continues billing under the seller’s provider number — no billing gap, but the buyer inherits the seller’s cost-report obligations, prior-period overpayment exposure, and any pending audit or investigation. Applying for new enrollment means the buyer’s new PC files its own CMS-855 enrollment forms and begins billing under its own provider number after approval, isolated from the seller’s exposure but with a processing gap that can extend for months. Neither path is categorically better; the choice depends on the specific facts.

How is Medi-Cal different from Medicare for a CHOW?

Medi-Cal has no uniform CHOW framework analogous to Medicare’s § 489.18. The analysis depends on which Medi-Cal category the target participates in — fee-for-service, Medi-Cal managed care through specific plans, or county-organized systems. Each has its own transition mechanics. For most non-licensee acquisition targets in the wellness segments, Medi-Cal participation is limited or absent, but where it exists the analysis warrants specific California healthcare counsel review.

What about commercial payors?

Commercial payor participation agreements are governed by the specific contract between the target and each payor. Most agreements require the payor’s written consent for assignment; some treat CHOW as a termination event requiring the buyer to apply as a new provider; and some allow novation through a three-party agreement that preserves the rate schedule and network status. The commercial payor transition planning has to run in parallel with the CPOM structural work and the Medicare CHOW planning, and can be a substantial fraction of the total closing timeline for practices with meaningful commercial payor mix.

My target offers superbills but doesn’t bill payors directly. Does the CHOW analysis apply?

The full CHOW framework does not apply because the target does not hold a Medicare or commercial payor participation agreement. But the superbill practice raises its own compliance question — the superbill represents to the payor that the services were rendered by an authorized provider, and where the target has been operating through a non-compliant structure, the historical superbills have carried an inaccurate representation. The buyer’s diligence should surface the superbill history and the buyer’s post-closing structure should issue superbills that accurately reflect the new physician-owned PC as the rendering provider.

Talk to a California Healthcare Acquisition Attorney

Bay Legal, PC represents non-licensee buyers of California treatment businesses through pre-LOI structural counsel, CPOM diligence, and payor-transition analysis. If you are evaluating a target with Medicare, Medi-Cal, or commercial payor participation, call (650) 668-8000 or schedule a consultation at baylegal.com/contact.