Foundation, Structure, and Building Exterior Contractors (U.S.) — NAICS 2381

A Histometrics rollup primer for public-market and private investors. NAICS (the North American Industry Classification System) is the standard the U.S. government uses to group businesses by activity. This is a four-digit industry group — one rung above the five-digit industries and two above the six-digit national industries where the leaf-level detail lives.

1. Overview

NAICS 2381 is the group of specialty-trade subcontractors who put up a building's skeleton and skin — the crews who pour its foundation, raise its structural frame, lay its brick and block, install its windows and curtain walls, and cover its roof and sides. These are the trades that arrive after the site is cleared and before the interior fit-out begins. Almost all of the work is subcontracted from a general contractor (GC), developer, or homebuilder; a slice of repair-and-remodel (R&R) work is sold straight to property owners.[1]

For an investor, three facts define the whole group. First, it is large and central to the construction economy: on this level's own federal figures, roughly $266 billion of annual receipts, ~103,000 firms, and ~959,000 workers.[2][3] Second, it is almost entirely private and extraordinarily fragmented — there is no clean, publicly traded pure-play in any of the eight child trades, so public-market investors reach the theme only indirectly, through the building-products makers, distributors, and diversified contractors that sit outside this code. Third, and most useful, the eight children are not one business — they run on different demand engines, from the earliest-cycle new-build work (foundations, framing, structural steel) to the most defensive replacement work (roofing, siding). The real value of looking at 2381 as a group is seeing how those pieces contrast. That is where this primer leads.

2. What's inside — the eight child industries, and how they differ

NAICS 2381 contains eight five-digit industries, each with a single six-digit national industry beneath it (so "23811" and "238110" describe the same businesses). They are cousins, not competitors: a poured-concrete firm and a roofer rarely bid against each other. What they share is a position on the building — foundation, frame, or exterior — and a common economic DNA (project-based, fixed-price, labor-driven, thin-margin). What they don't share is the cycle they ride, the size of the typical firm, or how an outside investor can touch them.

The contrast table below is the heart of this page. Revenue shares are of this level's $266.4 billion of 2022 receipts; ownership and demand notes are distilled from the eight child primers.[2][3]

Read the table top-to-bottom and the group's shape jumps out. The two heavyweights sit at opposite ends of the cycle. Poured concrete — the biggest slice at ~30% — is the most cyclical and early-cycle trade in the group, the first crew on a new site and the first cut when a project slips. Roofing — the second biggest at ~26% — is the most defensive, because four-fifths of its work is replacing worn-out roofs regardless of the economy. Together those two are more than half the entire level, so an investor who understands only those two understands the bulk of NAICS 2381. The middle of the group (framing, masonry, structural steel, glass) is where the trade characters diverge most sharply — homebuilding-levered framing next to structurally declining masonry next to data-center-levered steel and glass.

The scope boundaries are worth stating once for the group, because they explain why the dollar figures are a floor (see §3). NAICS 2381 covers the installation service, not the manufacturing of the materials — ready-mix concrete, structural steel, brick, glass, shingles, and siding are all made under separate manufacturing codes, and their much larger value is booked there. It also excludes heavy-civil highway and bridge concrete (237-series), interior trades (drywall, tile, finish carpentry), electrical work including rooftop solar (238210), and the plumbing/HVAC/mechanical trades. When a homebuilder or GC self-performs foundation, framing, or exterior work with its own crews, that activity is booked to the builder, not here.[1]

3. Size — this level's rollup figures

These are our ingested ground-truth federal statistics for NAICS 2381 as a whole. They combine the 2023 County Business Patterns (CBP, the Census Bureau's annual count of employer establishments) with the 2022 Economic Census (its every-five-years benchmark for firms, receipts, and concentration), so they are a size profile, not a single comparable annual series.[2][3]

A few things fall straight out. The average firm is tiny — about $2.6 million of receipts and roughly nine employees per establishment — and average pay runs near $68,000 per worker per year.[2][3] The group is seasonal: first-quarter payroll ($14.16 billion) is only ~22% of the annual total, well below a flat 25% quarter, the fingerprint of outdoor trades that slow in a northern winter (you cannot pour concrete or lay brick in a hard freeze).[2] And it is almost perfectly fragmented: the four largest firms hold just 1.8% of revenue, the top fifty only 8.2%, and the HHI — a 0–10,000 concentration index where anything under 1,500 is already "unconcentrated" — is 1.9, about as close to textbook perfect competition as any large industry group in the economy.

That group-level HHI of 1.9 is actually lower than every individual child's (the children range from ~9 for masonry to ~27 for the residual "Other" trade). That is not a paradox: aggregating eight largely non-competing trades dilutes any one firm's dominance across the whole group, so the biggest concrete contractor is a rounding error against roofing, framing, and glass combined. The practical takeaway is the same at every level — this is a private-market, owner-operator industry, not an oligopoly.

Here is how the group breaks down by child, which makes the contrast quantitative:

Two structural differences stand out. Structural steel and precast has the biggest average firm (~$5.0 million of receipts, ~$75,000 pay per worker) because steel erection is capital- and skill-heavy ironworker-and-crane work; siding and masonry have the smallest (~$1.3–1.6 million), the most atomized, lowest-barrier corners. And masonry is heavier by workers than by dollars — ~15% of the group's employment but ~11% of its revenue — the signature of an especially labor-intensive, low-revenue-per-worker trade. Siding shows the highest CR4 (11.1%) even though it is one of the smallest children, a hint that consolidation there has already moved further than the group average.

Undercount caveat — it matters a lot here. Every figure above counts only employer establishments with paid payroll. It excludes the self-employed, no-payroll sole proprietors, day-labor crews, and 1099 "independent" installers — and these trades are unusually skewed toward exactly those operators. The gap is largest in roofing (third-party sources that fold in nonemployers count on the order of ~96,000 businesses versus the ~24,000 employer firms here), framing (a very large population of self-employed carpenters and small crews), and siding (private research puts the true contractor-services market nearer ~$18 billion vs. the ~$10.8 billion counted).[2][7] On top of that, foundation, framing, and exterior work that homebuilders and GCs self-perform is booked to them, not here, and the "Other" residual quietly captures activity that spills across the sibling trades. Read $266 billion as the employer-core floor of a materially larger real economy, not a ceiling — the revenue totals are more reliable than the business head-counts, and small/individual ownership dominates.

4. Investable universe — where value concentrates across the children

The single most important fact for a public-market investor is the same in all eight children: there is no large, clean, U.S.-listed pure-play foundation, structure, or exterior contractor. The trade lives in private hands. Virtually every firm sits under the Small Business Administration's (SBA) size standard of about $19 million in average annual receipts, so the industry qualifies almost entirely as small business.[5] Value therefore concentrates in two ways an investor must treat differently.

By firm size, within each trade. In every child, the money and complexity sit with the larger, engineering-heavier, better-bonded firms — structural curtain-wall specialists in glazing, big commercial concrete contractors, national roofing platforms — while a long tail of small residential and repair shops holds the count. The competitive top tier is overwhelmingly private and frequently employee-owned: in concrete, Baker Construction (ranked the #1 U.S. concrete contractor for 17 straight years) and Lithko; in roofing, Tecta America (the #1 U.S. roofer), CentiMark, and Baker Roofing; in steel/precast, W&W|AFCO Steel, High Companies, Tindall, and Metromont; in masonry, Sun Valley Masonry and Western Specialty Contractors — none remotely large enough to move the group's ~$266 billion needle.[19]

By where public capital can actually touch it — always one step removed, and outside NAICS 2381. Because the contractors are private, listed exposure runs through the suppliers, distributors, and diversified builders around them. Reserving tickers for this section:

• Materials that cut across many of the trades — aggregates, cement, and ready-mix: Vulcan Materials (VMC), Martin Marietta (MLM), CRH plc (CRH), Eagle Materials (EXP), Knife River (KNF), Cemex (CX). These carry different economics from the contractors: quarries, pricing power, and capital intensity, not thin-margin labor.[20]
• Trade-specific building products — roofing: Owens Corning (OC), Carlisle (CSL), Amrize (AMRZ), Saint-Gobain (SGO); siding and framing: James Hardie (JHX), Louisiana-Pacific (LPX), Westlake (WLK), Weyerhaeuser (WY), Builders FirstSource (BLDR), UFP Industries (UFPI), Simpson Manufacturing (SSD); restoration/coatings: RPM International (RPM).[20]
• Distribution — QXO (QXO, which absorbed Beacon Roofing Supply), Home Depot (HD, owner of the SRS/GMS pro arms), Lowe's (LOW), with ABC Supply and US LBM as large private peers.[20]
• Homebuilders (demand-side proxy for framing and foundations) — D.R. Horton (DHI), Lennar (LEN), PulteGroup (PHM), NVR (NVR).[20]
• The nearest thing to listed contractor exposure — Apogee Enterprises (APOG) in glazing; INNOVATE Corp. (VATE, whose DBM Global is the largest U.S. steel fabricator-erector); Smith-Midland (SMID) in precast; Concrete Pumping Holdings (BBCP); Installed Building Products (IBP); FirstService (FSV); Tecnoglass (TGLS); and diversified E&C names that self-perform structural work — Sterling Infrastructure (STRL), Primoris (PRIM), MasTec (MTZ), Tutor Perini (TPC), Granite Construction (GVA), Orion Group (ORN). Every one of these is a partial or diluted handle — value the parent for what it actually is, not as a pure specialty contractor.[20]

The honest summary: public investors buy the supply chain and the demand side; the trade itself — the ~$266 billion of contractor value — is a private-market opportunity.

5. How the money works

Across all eight children the economic engine is the same: project-based, fixed-price subcontracting. A contractor bids a lump sum (or unit price — dollars per cubic yard poured, per square of roof, per square foot of siding or framing, per ton of steel erected), then earns the spread between that price and its actual cost of materials, field labor, and overhead. Revenue is recognized over time as the job progresses (percentage-of-completion). There is no recurring subscription revenue and, in a field this fragmented, almost no pricing power.

Because the price is fixed at bid and the work is often irreversible, the central operating risk is margin fade — labor overruns, weather delay, material inflation, or a mis-priced change order eating a job's profit. Gross margins run roughly 20–35% but net margins after overhead, insurance, bonding, and owner pay typically land in the mid-single digits to low teens, so estimating discipline and crew productivity, not scale, decide who makes money. The right input-cost gauges are the Bureau of Labor Statistics (BLS) Producer Price Indexes (PPI) for ready-mix concrete, structural steel, aluminum, brick, asphalt, and lumber — plus diesel — not the factory-capacity or same-store metrics used for manufacturers and retailers.

Two features shape returns in every child. First, it is a working-capital business: contractors buy materials and pay crews before the customer pays, and owners hold back retainage (commonly 5–10% of each bill) until the job is complete, so cash flow lags accounting profit and mechanics-lien rights matter. Second, surety bonding capacity effectively caps how large a project a firm can chase, which — together with a clean safety record (the insurance Experience Modification Rate) — is why larger, better-capitalized operators can pursue the bigger, better jobs. Where the children differ is the mix: roofing and siding lean on higher-margin, homeowner- and insurance-funded R&R; framing and foundations lean on lower-margin, higher-volume builder work; steel, precast, and curtain wall lean on large, lumpy, technically demanding commercial contracts.

6. Demand drivers

Demand for the group is, at bottom, the volume of things being built and maintained — but the eight children pull from different reservoirs, which is why the group as a whole is steadier than any one trade:

• New non-residential construction — the current standout. Data centers and the power infrastructure behind the artificial-intelligence buildout are the fastest-growing construction segment and the biggest tailwind for the concrete, structural-steel, precast, glass, and "Other" trades.[7][8] Factory reshoring (semiconductor and battery plants) added a wave that cooled from its 2023–24 peak, and warehouses, hospitals, schools, and stadiums provide the steady base.
• New residential construction. Foundations and framing are the first trades on a new house, making them the most rate-sensitive and early-cycle part of the group; single-family activity has been soft with mortgage rates near 6.5%.[6]
• Repair, remodel, and replacement — the defensive ballast. Roofing (~80% replacement), siding, and masonry restoration ride an aging building stock and record homeowner-improvement spending (recently near ~$524 billion), much of it non-discretionary and partly insurance-funded after storms.[15][16] This is what keeps the group from moving as violently as new construction alone.
• Weather and insurance. Hail and wind drive claim-funded roof and siding replacement — U.S. insurers paid over $31 billion in wind/hail residential roof claims in 2024 — a partly counter-cyclical demand pool.[16]
• Public infrastructure and codes. The 2021 Infrastructure Investment and Jobs Act (IIJA) supports structural and civil concrete and steel demand, with much still to be spent; tightening energy codes pull glazing and exterior work toward higher-value, higher-performance products.[8]
• Financing conditions. Interest rates gate both homebuying and debt-financed commercial development, which is why the new-build children are sharply cyclical while the replacement children are not.

Leading indicators worth watching for the group: housing starts and permits, monthly construction spending, the American Institute of Architects' (AIA) Architecture Billings Index (ABI, where below 50 signals contraction), contractor backlog, and Harvard's Leading Indicator of Remodeling Activity (LIRA) for the R&R side.[6][15]

7. Regulation

None of these trades is rate-regulated or entry-licensed at the federal level; regulation targets worker safety and building integrity, and it is broadly common across the group:

• Worker safety (Occupational Safety and Health Administration, OSHA). The load-bearing rules recur trade to trade: respirable crystalline silica (29 CFR 1926.1153, central to concrete, masonry, and fiber-cement cutting); fall protection (generally triggered at six feet, the defining hazard for roofing, framing, siding, and glazing); steel erection (Subpart R, one of the most fatal-injury-prone trades); and trenching, scaffold, and concrete/masonry standards. Quality certifications — from the American Institute of Steel Construction (AISC), American Welding Society (AWS), and Precast/Prestressed Concrete Institute (PCI) — are effectively table stakes to bid larger structural jobs.[10]
• Environmental (Environmental Protection Agency, EPA). Construction stormwater permitting and concrete-washout rules; the Lead Renovation, Repair and Painting (RRP) rule on pre-1978 buildings, relevant to masonry, siding, and roofing restoration.[11]
• Building and energy codes. The model International Building and Residential Codes (IBC/IRC) and the International Energy Conservation Code (IECC)/ASHRAE 90.1 govern how each element is built and, for glazing especially, drive demand toward higher-performance products; they reference trade standards such as ACI 318 (concrete) and TMS 402/602 (masonry).[12]
• Labor and wages. Davis-Bacon prevailing wages on covered federal work; state-by-state contractor licensing, bonding, and lien rules; and — acutely for this immigrant-heavy workforce — Form I-9/E-Verify employment-eligibility enforcement.[13]
• Trade policy. Section 232 steel tariffs (raised to 50% in June 2025) and cement/aluminum tariffs bear directly on input costs for the steel, precast, concrete, and glazing trades.[14]

The practical investment point: compliance depth — safety systems, bonding capacity, certifications — is itself a competitive moat that favors the larger, better-run operators.

8. Consolidation

NAICS 2381 is one of the most fragmented parts of the U.S. economy (group CR4 of 1.8%, HHI of 1.9), which is precisely why it has become a magnet for consolidation.[3] Two forces are at work, and they are running at different speeds across the children:

• Private-equity (PE) roll-ups. Sponsors are buying founder-owned local firms at mid-to-high-single-digit multiples of EBITDA (earnings before interest, taxes, depreciation, and amortization; specialty-trade deals have recently run ~5.7x–8.2x) and centralizing marketing, procurement, estimating, and bonding.[17] Roofing is furthest along — PE-backed platforms grew from ~17 in early 2023 to ~56 by end-2024 — with siding/exterior-services roll-ups close behind; the residual "Other" trades saw subcontractor M&A jump ~39% in 2025; and masonry is barely starting, because a labor-intensive, seasonal, low-margin trade with no recurring revenue is a less attractive target.[18][17]
• Employee-stock-ownership plans (ESOPs) and family successions. An aging owner base with thin succession pipelines makes ownership transfer a steady deal-supply engine; many of the largest concrete, glazing, and steel firms are already employee-owned.

But note where consolidation is really happening. In framing especially, the consequential concentration is above the installers — in factory-made trusses and wall panels, where prefabrication has climbed to an estimated 30–40% of the market and distributors are rolling up component plants. In roofing and siding, national scale has arrived first in distribution (largely public) rather than contracting (still local). A binding brake on all of it is that heavy, hard-to-transport materials (wet concrete, structural steel, precast, brick) keep competition regional, and the real growth constraint is skilled labor, not demand or capital. Roll-ups also carry genuine integration risk — estimating systems, union relationships, local licenses, and safety cultures do not merge as cleanly as financial statements.

9. Risks

The eight children share one risk register, which is really the risk register of fixed-price construction subcontracting:

• Cyclicality and interest-rate sensitivity — heaviest on the new-build children (foundations, framing, structural steel), cushioned by the replacement children (roofing, siding, masonry restoration).
• Fixed-price execution risk — one mis-estimated job on thin margins can erase profit, and much of the work is irreversible (rework destroys margin).
• Skilled-labor shortage — the binding constraint across the group, worsened by an aging workforce and immigration enforcement of a heavily foreign-born trade.[9]
• Input-cost and tariff volatility — ready-mix, steel (50% Section 232 tariffs), aluminum, cement, lumber, asphalt, and diesel, hitting hardest on fixed bids without escalation clauses.[14]
• Thin margins and no pricing power in a near-perfectly-competitive market.
• Working-capital, retainage, and counterparty risk — contractors pay first and collect last; GC, developer, or insurer distress flows straight to the subcontractor.
• Safety and warranty liability — silica, falls, trench and steel-erection hazards, and latent defects (foundation cracks, facade water intrusion).[10]
• Substitution — factory prefabrication (trusses, panels, modular, precast) moving labor off-site, and cheaper claddings taking share from field-laid masonry.
• Consolidation / roll-up execution risk — integration failure and leverage against volatile cash flows.
• Data and proxy risk for investors — employer-only federal statistics undercount the small-operator reality (§3), and every listed proxy reflects the trade only partially (basis risk).

10. How to invest, and the outlook

Public-market investors should start by accepting that they cannot buy the trade directly, then choose their angle:

• For the new-build / data-center theme, the cleanest liquid handles are the aggregates and cement producers (VMC, MLM, CRH, EXP, KNF) and the diversified E&C names that self-perform structural concrete and steel (STRL, PRIM, MTZ, TPC, GVA); the nearest operating proxies are ORN, BBCP, VATE/DBM, SMID, and APOG.[20]
• For the defensive replacement theme, the roofing- and siding-materials makers and distributors (OC, CSL, AMRZ, JHX, LPX, WLK, BLDR, QXO, HD) track re-roof and remodel volumes with far less cyclicality.[20]
• For housing-cycle exposure, the homebuilders (DHI, LEN, PHM, NVR) and framing-component makers (BLDR, UFPI, SSD).[20]

In every case, size the position to the actual exposure — a quarry, a shingle mill, or a distributor is not a specialty contractor, and its margins, capital intensity, and pricing power differ.

Private investors — where the industry genuinely lives — own or operate regional contractors, back or build PE roll-up platforms, buy into ESOP-style successions, or provide equipment leasing and private credit against receivables and backlog. The best targets share the same fingerprints regardless of trade: disciplined job-cost and work-in-progress accounting, a clean safety record, adequate bonding, a trained crew in a labor-short market, low customer concentration, and a real succession plan. Because the group is so fragmented, sourcing and integration — not underlying demand — are the hard part, and the diligence priority is always job-level economics.

Outlook. A large, fragmented, labor-scarce set of trades that is unusually bifurcated into 2026–2027. The strongest pull is on the children levered to data centers, power, and large commercial structural work — concrete, structural steel, precast, glazing, and the residual metal/facade trades. The replacement-driven children — roofing and siding — offer the steadiest demand, backed by an aging building stock and insurance-funded storm work, with consolidation set to continue fastest there. The soft spots are the homebuilding-levered trades (framing, single-family foundations), waiting on lower mortgage rates, and structurally declining masonry, squeezed by substitution. Cutting across all of it: a deep skilled-labor shortage, volatile tariff-inflated input costs, and an accelerating PE-and-ESOP consolidation wave — all of which favor the larger, better-capitalized, more productive operators. For public investors the theme is best owned through the supply chain and the demand side; for private investors, it remains a hands-on, owner-operator business that rewards discipline over passive capital.

---

Sources

Consolidated from the eight child primers (NAICS 23811–23819); federal figures for this level are our own ingested ground-truth statistics.

1. U.S. Census Bureau, 2022 NAICS — Industry Group 2381 (Foundation, Structure, and Building Exterior Contractors) and its eight industries: definitions, scope, and cross-references. https://www.census.gov/naics/?details=2381&year=2022
2. U.S. Census Bureau, County Business Patterns, 2023 — NAICS 2381 (establishments, employment, annual and first-quarter payroll; employer-only coverage). https://www.census.gov/programs-surveys/cbp.html
3. U.S. Census Bureau, 2022 Economic Census — Concentration of Largest Firms, NAICS 2381 (firms, receipts, CR4/CR8/CR20/CR50, HHI). https://data.census.gov/table/ECNSIZE2022.EC2200SIZECONCEN
4. U.S. Census Bureau, County Business Patterns methodology and Nonemployer Statistics (employer-only coverage; exclusion of self-employed and no-payroll businesses). https://www.census.gov/programs-surveys/cbp/technical-documentation/methodology.html
5. U.S. Small Business Administration, Table of Small Business Size Standards (13 CFR 121.201) — NAICS 2381 subsector, ~$19 million average annual receipts. https://www.sba.gov/document/support-table-size-standards
6. U.S. Census Bureau, Monthly New Residential Construction and Monthly Construction Spending (2026) — starts, permits, and residential/nonresidential/public spending. https://www.census.gov/construction/nrc/current/index.html
7. IBISWorld, U.S. specialty-trade contractor industry reports (roofing, framing, masonry, glazing, siding — broader market sizes including nonemployers). https://www.ibisworld.com/united-states/
8. U.S. Department of Energy, Report Evaluating Increase in Electricity Demand from Data Centers (2024); Associated General Contractors of America, 2026 Construction Industry Outlook. https://www.energy.gov/; https://news.agc.org/economics/2026-construction-industry-outlook/
9. Associated Builders and Contractors / National Association of Home Builders / Associated General Contractors, 2026 construction workforce shortage and immigration-enforcement analyses. https://www.abc.org/News-Media/News-Releases
10. U.S. Occupational Safety and Health Administration, Respirable Crystalline Silica (29 CFR 1926.1153), Fall Protection (1926.501), Steel Erection (Subpart R), and concrete/masonry/excavation standards. https://www.osha.gov/laws-regs/regulations/standardnumber/1926
11. U.S. Environmental Protection Agency, Construction Stormwater (NPDES) and Lead Renovation, Repair and Painting (RRP) Program. https://www.epa.gov/npdes/stormwater-discharges-construction-activities
12. International Code Council, 2024 International Building/Residential Codes and International Energy Conservation Code (references ACI 318 concrete and TMS 402/602 masonry standards). https://codes.iccsafe.org/
13. U.S. Department of Labor, Davis-Bacon and Related Acts. https://www.dol.gov/agencies/whd/government-contracts/construction
14. U.S. trade-policy reporting, Section 232 steel tariffs (raised to 50%, June 2025) and cement/aluminum tariff impacts on construction input costs (Gordian and industry cost trackers). https://www.constructiondive.com/
15. Joint Center for Housing Studies of Harvard University, Leading Indicator of Remodeling Activity (LIRA) and remodeling-spending releases (~$524 billion). https://www.jchs.harvard.edu/
16. TAMKO / industry reporting, U.S. wind and hail residential roof insurance claims (>$31 billion, 2024). https://www.businesswire.com/
17. Capstone Partners, Construction Services M&A Update (2025) — NAICS 238 specialty-trade TEV/EBITDA ~5.7x–8.2x; Construction Dive / PrivSource, private-equity roll-up activity, 2024–2025. https://www.capstonepartners.com/insights/article-construction-ma-update/
18. Roofing Contractor (BNP Media) / AXIA Advisors, Private-equity roofing platform counts (~17 in early 2023 to ~56 by end-2024) and roll-up trackers (2025). https://www.roofingcontractor.com/
19. Engineering News-Record Top 600 Specialty Contractors; Siteline Top Concrete Contractors; USGlass Top 50 Glaziers (largest private operators by reported revenue, 2024–2025). https://www.enr.com/toplists
20. Company filings and investor relations for the listed proxies cited in §4 and §10 — aggregates/cement (VMC, MLM, CRH, EXP, KNF, CX), building products (OC, CSL, AMRZ, SGO, RPM, JHX, LPX, WLK, BLDR, UFPI, SSD), distribution (QXO, HD, LOW), homebuilders (DHI, LEN, PHM, NVR), and contractor-adjacent names (APOG, VATE, SMID, BBCP, IBP, FSV, TGLS, STRL, PRIM, MTZ, TPC, GVA, ORN). U.S. Securities and Exchange Commission EDGAR: https://www.sec.gov/edgar