The legal structure of your medspa—who owns it, who operates it, and how they relate—is not a compliance afterthought. It is the foundation. The Corporate Practice of Medicine (CPOM) doctrine, enforced unevenly across states, prohibits non-licensed practitioners from owning or controlling the medical decisions of a medical practice in roughly half the country. For medspa owners, this creates a hard constraint: in CPOM states, a physician or nurse practitioner must own the practice or hold controlling interest, even if you are the one running it operationally. Non-CPOM states permit lay ownership. The Management Services Organization (MSO) structure—a workaround where a non-medical entity provides administrative services to a separately owned medical practice—has become the standard tool for PE-backed roll-ups and national chains to scale across state lines while respecting CPOM. Understanding your state's rule, and the MSO model's mechanics and limits, is essential before you take capital, hire investors, or expand.