Offices of Physicians — U.S. Industry-Group Primer

North American Industry Classification System (NAICS) 2022 code 6211 — an industry group (4-digit) that contains exactly one child industry: 62111, Offices of Physicians.

A Histometrics rollup primer for public-market and private investors. Because this level has only one child, it is a short pass-through page: it states this level's own federal statistics and points you to the 62111 primer for full detail.

1. Overview

This is the business of doctors — physicians holding a Doctor of Medicine (MD) or Doctor of Osteopathic Medicine (DO) degree — seeing patients in their own offices rather than in hospitals: primary-care practices, specialist offices, multispecialty groups, and psychiatrists' practices. Taken together it is one of the largest single industries in the U.S. economy by employment, and it is the retail front end of roughly a fifth of all national health spending [6].

At the 4-digit level, 6211 is effectively identical to its one child, 62111. NAICS gives "Offices of Physicians" both an industry-group code (6211) and an industry code (62111) that cover the same activity; there is no second sibling industry to roll up. So the size, economics, demand drivers, and regulation of 6211 are the size, economics, demand drivers, and regulation of 62111. For anything beyond the summary below — the investable names, the two-part split between general medicine and psychiatry, and the full risk and regulatory picture — read the 62111 primer, which is the substantive page for this branch of the taxonomy.

2. What's inside — and why the level equals its one child

NAICS is a nested system: each 4-digit industry group divides into one or more 5-digit industries. Most groups have several children; 6211 has just one, 62111. When a group and its single child describe the same activity, the group is a pass-through — its statistics simply equal the child's.

The real structure worth knowing sits one level down, inside 62111, which itself splits into two very different businesses fused into one code:

• 621111 — Offices of Physicians (except Mental Health Specialists) is the whale: family medicine, internal medicine, cardiology, orthopedics, dermatology, oncology, surgery, and the rest — about 98% of receipts, with economics increasingly built around Medicare and value-based-care risk contracts.
• 621112 — Offices of Physicians, Mental Health Specialists (psychiatrists) is a rounding error by revenue (~2%) but a structurally distinct, faster-growing, supply-constrained specialty with its own regulatory pressure points (controlled-substance telehealth) and its own investable platforms.

That two-part split is the substance of this branch, and the 62111 primer develops it in full. The 6211 page exists only to carry the 4-digit rollup figures.

The level excludes a lot of adjacent care: dentists, chiropractors, optometrists, podiatrists, and non-physician mental-health practitioners (psychologists, counselors, social workers — NAICS 621330, where most talk therapy lives); outpatient care centers (6214); labs (6215); home health (6216); and — most importantly for sizing — hospitals (622) [3].

3. How big it is (this level's rollup)

Federal business statistics for NAICS 6211 (our ground-truth file for this level) — identical, as expected, to 62111:

Read these carefully. The figures mix reference years (2022 receipts/firms vs. 2023 employment/payroll) and are not a single-period snapshot. Receipts are gross revenue, not profit. The 2.77 million "employees" counts everyone on office payrolls — nurses, medical assistants, front-desk and billing staff — not just physicians. Concentration is essentially nil: an HHI of 18 is effectively zero on the 0–10,000 antitrust scale (regulators treat anything below 1,500 as "unconcentrated"), and the four largest firms hold just 6.1% of receipts. The real concentration is local, not national (Section 8).

Undercount caveats. These are employer-only counts. County Business Patterns and the Economic Census concentration tables count establishments with paid employees and exclude most government-run operations [1][2]; solo, cash-only physicians with no staff — a meaningful slice of psychiatry — are "nonemployer" businesses tracked separately, and our supplied file has no 6211 nonemployer add-on, so no total for the full self-employed universe is stated here [4]. Where small and individual ownership dominates, treat the firm and establishment counts as a floor. Separately, the 6211 line understates total physician-delivered care: as hospitals buy up practices, that revenue reclassifies into hospitals (622) or outpatient care centers (6214), which is why this level's $640.4 billion of office receipts [2] sits far below the $978 billion the federal health accounts attribute to "physician and clinical services" nationally in 2023 [6].

4. Investable universe (where value concentrates)

There is no clean, pure-play public index for this level, and most of the real economics sit in private hands. Because 6211 equals 62111, the investable map is the child's; in brief, value concentrates along the two-part split:

• General-medicine side (621111) — where the dollars are: physician-enablement / value-based-care groups (the nearest direct bet), plus employed-physician exposure buried inside far larger insurers and integrators, and specialty management-services platforms held inside broader businesses.
• Psychiatry side (621112) — where the scarcity is: small listed outpatient behavioral platforms and adjacent facility, digital, and pharma names.

The 62111 primer lists the specific tickers, private platforms, and non-tradable owners (health systems, Kaiser Permanente's Permanente Medical Groups, private-equity roll-ups, telepsychiatry networks). The one takeaway at this level: you cannot buy "the level" as a single security.

5. How the money works

Two engines run under one code. General-medicine offices (621111) are at core fee-for-service (FFS) billing shops priced off Medicare's Physician Fee Schedule — relative value units (RVUs) times a national conversion factor — with a fast-growing value-based-care / capitation overlay in which a group takes a fixed per-member-per-month (PMPM) payment (usually from a Medicare Advantage plan) and keeps the spread over actual medical cost; the key ratio is the medical loss ratio. Psychiatry offices (621112) earn one visit at a time, are light on equipment, and turn on clinician cost and payer mix — psychiatry is the specialty least likely to take insurance, so a large minority run cash / out-of-network. Across both, outside capital typically enters through a management-services organization (MSO) that owns billing, technology, staffing, and real estate while a physician-owned professional entity holds the clinical license. Full mechanics are in the 62111 primer.

6. Demand drivers

Demand across the level is durable and demographically tailwinded. The population age 65 and older reached 61.2 million in 2024 — 18.0% of all Americans [9], and older patients use far more physician care, so rising Medicare enrollment is the single biggest structural tailwind. Chronic-disease prevalence, insurance coverage, a persistent doctor-supply shortage, and the ongoing shift of care from hospitals into lower-cost office and telehealth settings all add to it. The two children lean on different specifics — Medicare Advantage penetration for general medicine, rising diagnosed prevalence against a hard clinician-supply ceiling for psychiatry — detailed in the 62111 primer.

7. Regulation

This level sits inside one of the most heavily regulated revenue models in the economy. The binding levers: the annual Medicare Physician Fee Schedule and its conversion factor (which effectively sets the industry's price floor, with no automatic inflation update); Corporate Practice of Medicine (CPOM) doctrines, which in roughly two-thirds of states force outside capital to enter through an MSO rather than owning practices outright; and the fraud-and-abuse, privacy, and billing regime — Stark Law, the Anti-Kickback Statute, the Health Insurance Portability and Accountability Act (HIPAA), and the No Surprises Act. Psychiatry adds a distinct lever — Drug Enforcement Administration (DEA) / Ryan Haight rules on telehealth prescribing of controlled substances, currently under temporary flexibilities through December 31, 2026. The 62111 primer covers each in detail [11][12].

8. Consolidation

At the national level this is about as unconcentrated as an industry gets — CR4 6.1%, CR50 22.8%, HHI 18 [2] — but the national picture hides intense local consolidation, because patients, physicians, referral relationships, and payer contracts are all geographically specific. Independent private practice is shrinking as hospitals and health systems (now employing 34.5% of physicians [7]), vertically integrating insurers, and private-equity specialty roll-ups acquire practices. Antitrust attention — the Federal Trade Commission's 2025 physician-market study [11] and the Welsh Carson / U.S. Anesthesia Partners settlement [12] — has focused on the general-medicine side, with states now adding merger-notification and private-equity/MSO oversight . Details, including the newer psychiatry-side vehicles, are in the 62111 primer.

9. Risks

The material risks are the child's: annual Medicare reimbursement pressure with no built-in inflation update; a cost squeeze in which clinician compensation is the dominant line (and, in psychiatry, the binding constraint given a structural shortage); value-based-care / Medicare Advantage downside when medical costs run above premium (mostly 621111); telehealth-policy reversal on controlled-substance prescribing (mostly 621112); payer concentration and revenue-cycle risk; regulatory and antitrust scrutiny of CPOM/MSO structures; and integration and leverage risk in debt-funded roll-ups. A data limitation also applies at this level: public parents rarely disclose clean NAICS-level revenue, and federal employer statistics exclude the smallest, nonemployer, and government-run practices (Section 3). See the 62111 primer for the full list.

10. How to invest, and the outlook

Because 6211 equals 62111, the investment routes are the child's: on the public side, sort by which sub-business you want — general-medicine value-based-care and integrator names, or the small psychiatry platforms and adjacent operators; on the private side (where most of the real economics live), direct practice ownership and buy-ins, private-equity/MSO platforms, and medical-office real estate (directly or via healthcare real estate investment trusts, REITs). Specific tickers, private platforms, and a diligence checklist are in the 62111 primer.

Outlook. Constructive but selective. The structural tailwind — an aging population needing more care — is not in doubt; the open questions are who captures the margin and whether regulators let the current owners keep it. The 2026 Medicare fee schedule delivers the first meaningful raise in years, modestly easing FFS pressure, while consolidation advances against a rising wall of state regulation. Our supplied federal file for NAICS 6211 contains no revenue-growth forecast, margin benchmark, or complete ownership census, and none is asserted here [1][2].

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Sources

(Numbering follows the 62111 primer, from which this rollup is synthesized; see that page for the full source list.)

1. U.S. Census Bureau, County Business Patterns 2023 (NAICS 6211 / 62111: establishments 218,066; employment 2,771,935; annual payroll ~$290.9B; Q1 payroll ~$68.2B). https://www.census.gov/programs-surveys/cbp.html
2. U.S. Census Bureau, 2022 Economic Census — Concentration / Comparative Statistics (NAICS 6211 / 62111: receipts $640.4B; firms 149,963; CR4 6.1% / CR8 9.3% / CR20 15% / CR50 22.8%; HHI 18). https://www.census.gov/programs-surveys/economic-census.html
3. U.S. Census Bureau, North American Industry Classification System — 6211 / 62111 / 621111 / 621112 (scope and cross-references), 2022. https://www.census.gov/naics/?details=62111&input=62111&year=2022
4. U.S. Census Bureau, Nonemployer Statistics (employer-only coverage of CBP/Economic Census; no 6211 nonemployer figure in the supplied file). https://www.census.gov/programs-surveys/nonemployer-statistics.html
5. Centers for Medicare & Medicaid Services, National Health Expenditure Fact Sheet (2023 data; physician and clinical services $978B, ~20% of health spending). https://www.cms.gov/data-research/statistics-trends-and-reports/national-health-expenditure-data/nhe-fact-sheet
6. American Medical Association, Physician Practice Benchmark Survey — Physician Practice Arrangements in 2024 (private practice 42.2%, hospital-owned 34.5%, private-equity ~6.5%). https://www.ama-assn.org/about/research/physician-practice-benchmark-survey
7. U.S. Census Bureau, Older Adults Outnumber Children in 11 States (65+ population 61.2 million, 18.0% in 2024), 2025. https://www.census.gov/newsroom/press-releases/2025/older-adults-outnumber-children.html
8. Centers for Medicare & Medicaid Services, Calendar Year 2025 Medicare Physician Fee Schedule Final Rule (conversion factor $32.35), 2024. https://www.cms.gov/newsroom/fact-sheets/calendar-year-cy-2025-medicare-physician-fee-schedule-final-rule
9. Centers for Medicare & Medicaid Services, Calendar Year 2026 Medicare Physician Fee Schedule Final Rule (CMS-1832-F) (dual conversion factors $33.57 / $33.40; +2.5% statutory update), 2025. https://www.cms.gov/newsroom/fact-sheets/calendar-year-cy-2026-medicare-physician-fee-schedule-final-rule-cms-1832-f
10. American Medical Association, Corporate Practice of Medicine overview, and Milbank Memorial Fund, How MSOs Are Reshaping Physician Practices (CPOM doctrine; MSO structures; state private-equity/MSO oversight trends). https://www.ama-assn.org/practice-management/private-practices/corporate-practice-medicine; https://www.milbank.org/publications/the-corporate-backdoor-to-medicine-how-msos-are-reshaping-physician-practices/
11. U.S. Federal Trade Commission, First Research Published from Physician 6(b) Study, 2025. https://www.ftc.gov/enforcement/competition-matters/2025/06/first-research-published-physician-6b-study
12. U.S. Federal Trade Commission, FTC Secures Settlement with Private Equity Firm in Antitrust Roll-Up Scheme Case (Welsh Carson / U.S. Anesthesia Partners), 2025. https://www.ftc.gov/news-events/news/press-releases/2025/01/ftc-secures-settlement-private-equity-firm-antitrust-roll-scheme-case