The five rows below carry the operative statutory language verbatim, each quote pulled from the official code. This page is one state from the full state-by-state reference. Nothing here is legal, tax, or financial advice.
The five-part test in brief
Whether an ABA practice needs a professional entity is a stack of five questions. The licensing act is the gateway, because an unlicensed profession is generally not a professional service and an ordinary entity governs. The professional-entity statute supplies the form and the ownership rule that applies if that form is used. The scope definition decides whether ABA is actually inside that statute. The corporate-practice doctrine, a separate body of law that often lives in the medical practice act or case law rather than the entity statute, is usually what forces licensed ownership and pushes outside capital into a management company. And the fee-splitting and anti-remuneration rules constrain management-fee economics even where ownership is open. The rows below run those five against this state's actual code, quoting the operative language so the position rests on the statute.
Washington, provision by provision
Washington
Strict by doctrine, untested for ABA; the professional form is elective by statuteHolding: on the Supreme Court's stated test, a non-licensee-owned Washington LLC that employs licensed behavior analysts is practicing applied behavior analysis without legislative authorization. The entity statutes do not compel the professional form; the doctrine does, and it has not been tested against ABA. The conservative structure is a licensee-owned professional entity with a management company that does not employ the clinicians.
Yes. Washington licenses behavior analysts, licenses assistant behavior analysts, and certifies behavior technicians under Chapter 18.380 RCW, administered directly by the Department of Health with an advisory Applied Behavior Analysis Advisory Committee. Except as exempted, no person may engage in the practice of applied behavior analysis without a license or temporary license.
Conclusion. ABA is a licensed profession in Washington, the gateway for the entity questions below, but as the next axis shows, the gateway carries no mandatory entity form with it.
A professional entity is not required. Chapter 18.100 RCW permits, but does not compel, a licensed individual to organize a professional service corporation, and the statute's own text uses "may," not "shall." Where a professional service corporation is used, ownership is generally restricted to persons duly licensed to render the same professional services, but nothing forces a behavior analyst to use this form rather than an ordinary LLC or business corporation.
Conclusion. The entity statutes do not require a professional entity for ABA in Washington; the professional service corporation and professional LLC exist and are available on the same-profession election. Whether a standard LLC may lawfully render ABA is decided by the doctrine in axis four, not by these statutes.
Chapter 18.100 RCW is written broadly enough, "duly licensed or otherwise legally authorized to render the same professional services," that a Washington-licensed behavior analyst could elect to organize under it. But Chapter 18.380 RCW's own list of licensed health professions that may combine into a single professional service corporation under RCW 18.100.050(5)(a) does not include Chapter 18.380, meaning behavior analysts are not swept into that particular multi-profession combination privilege even though the single-profession election under RCW 18.100.050(1) remains available to them.
Conclusion. ABA reaches the elective professional service corporation form on its own, single-profession basis, but is not included in Washington's special multi-profession combination privilege, a narrow but real distinction from several other health professions in the state.
Ownership. Washington has no corporate-practice statute; the doctrine is judge-made and its scope is what the Supreme Court has said. In Columbia Physical Therapy, Inc. v. Benton Franklin Orthopedic Associates, PLLC, 168 Wn.2d 421 (2010), a unanimous court "adhere[d] to the traditional understanding that the corporate practice of medicine doctrine forbids employment of health care professionals by business entities or nonprofessionals absent legislative authorization," stated the test as "the practice of certain professions requires a license" and "a person or entity practices a profession by either directly engaging in statutorily defined conduct or by employing a licensed individual to engage in such conduct," and expressly rejected the argument that the doctrine restricts only ownership and not employment. The court found the legislative authorization for that physician-owned PLLC to employ physical therapists in the Professional Service Corporation Act itself. The doctrine descends from Morelli v. Ehsan, 110 Wn.2d 555 (1988), and State ex rel. Standard Optical Co. v. Superior Court, 17 Wn.2d 323 (1943), an optometry case. The Attorney General applies the Columbia formulation as the starting point of its own opinions, and SB 5387 / HB 1675 (2025 to 2026) would codify it. Applied to Chapter 18.380, the practice requires a license, the chapter contains no entity authorization and no employer exemption (RCW 18.380.030), and the only authorizations are the professional entities. No Washington court or agency has applied the doctrine to behavior analysis.
Clinical control. Under the doctrine, the act the law forbids is a non-licensee entity employing licensees, so a management company must not employ the behavior analysts, hold the PLLC's equity, or exercise its votes; it provides administration at a fixed fair-market-value fee. Chapter 18.380 keeps clinical practice with the licensees regardless of structure.
Conclusion. On the conservative reading this page adopts, the clinical entity should be a PLLC or PSC owned by licensed behavior analysts, with a non-licensee's capital in a management company. A non-licensee-owned standard LLC employing licensed behavior analysts carries corporate-practice exposure that has not been litigated; prevalence of that structure in Washington is evidence the doctrine has not been enforced against ABA, not that it does not apply.
Open ownership does not mean open money. Washington's Uniform Disciplinary Act, Chapter 18.130 RCW, applies to license holders across the health professions it covers and defines a broad category of unprofessional conduct, including acts of dishonesty or corruption relating to the practice of the profession, that a disciplining authority can reach even without a dedicated fee-splitting statute naming ABA specifically. Any ABA practice billing Washington Apple Health or commercial insurers remains fully subject to the federal Anti-Kickback Statute and Stark self-referral rules regardless of how the state disciplinary framework is read.
Conclusion. A management agreement should be priced at fair market value to satisfy the federal anti-kickback and Stark framework; confirm the current scope of Chapter 18.130 RCW's unprofessional-conduct provisions as applied to behavior analysts directly with the Department of Health before finalizing a management-fee structure.
ABA is a licensed profession in Washington under Chapter 18.380 RCW (axis one). The professional service corporation and professional LLC are elective by statute, and behavior analysts are excluded from the multi-profession combination privilege, though the single-profession election is available (axes two and three). Washington's corporate-practice doctrine, as stated by the Supreme Court in Columbia Physical Therapy, forbids a business entity from practicing any licensed profession through employees absent legislative authorization, and Chapter 18.380 supplies none; the doctrine is untested for ABA (axis four). The Uniform Disciplinary Act and the federal anti-kickback framework constrain management-fee structuring (axis five). Therefore the conservative structure is a licensee-owned PLLC or PSC with outside capital in a management company that does not employ the clinicians.
Outlook: how this verdict could change
Likelihood of change: Moderate. SB 5387 and HB 1675 in the 2025 to 2026 session would codify the doctrine as a prohibition on unlicensed entities owning practices or employing licensed providers; enactment would remove the "untested" qualifier. A Department of Health enforcement action or an Attorney General opinion addressing ABA would do the same.
What to watch. The codification bills, any Attorney General opinion applying the Columbia test to behavior analysis or a comparable master's-level profession, and any amendment to RCW 18.100.050(5)(a) adding Chapter 18.380 to the multi-profession combination list.
Disruption if it changes: High. Codification or an enforcement action would convert every non-licensee-owned Washington ABA LLC into a restructuring case; practices already built on a licensee-owned PLLC with a management company would carry over.
Where professional advice is essential, not optional
Verbatim statutory text is a starting point, not a conclusion. Statutes are amended, agencies issue rules that fill them in, and courts interpret them. Washington is a state where the entity statutes read as permissive and the case law does not, and the case law controls. This page was corrected in August 2026 after an earlier version classified Washington as open on the entity statutes alone without reading the corporate-practice doctrine as the Supreme Court has stated it. Use this page to locate the operative provisions and to speak from the source, then confirm the current text and citations against the official code and engage qualified Washington counsel before acting. Nothing here is legal, tax, or financial advice.
The provisions quoted here change and are interpreted by agencies and courts. The official Washington code and qualified Washington counsel are the authoritative sources. Neither this page nor any secondary source should be relied on in place of direct verification and professional advice.