Other Support Activities for Water Transportation (NAICS 488390)

A Histometrics industry primer for public-market and private investors

1. Overview

The North American Industry Classification System (NAICS) 488390 is the "everything else" bucket of the maritime-services world. It covers the specialist firms that keep ships and cargo moving but that don't fit the three named support niches — port operations, cargo handling (stevedoring), and navigation aids like pilotage. In practice this code is home to floating dry docks and routine ship repair/maintenance, ship scaling (scraping and surface prep outside a shipyard), marine cargo checkers and surveyors (independent inspectors who verify a vessel's condition or a cargo's quantity and damage), marine salvage and wreck-removal companies (the crews called when a vessel grounds, sinks, catches fire, or blocks a channel), ship dismantling and recycling (shipbreaking) operators, and lighterage (barges that shuttle cargo to and from ships too large to fully enter a port).[1]

Why it matters to an investor: this is niche, unglamorous infrastructure plumbing for global trade. Parts of it enjoy regulated, recurring demand — federal law forces certain tanker owners to keep salvage firms on retainer, and inspection cadences are set by rule — while other parts deliver episodic windfalls, since a single large casualty can be a nine-figure job.[20] It is also almost entirely a private-market industry. There is essentially no U.S. pure-play public stock here; public-market investors reach it only indirectly, through diversified inspection-and-certification companies, ship repairers, and marine-services groups. Private investors — family owners, strategic acquirers, and private equity — own the meaningful assets.

2. What it is and how it's structured

The U.S. Census Bureau defines 488390 as establishments "primarily engaged in providing services to water transportation" other than port and harbor operations, marine cargo handling, and navigational services to shipping.[1] Official illustrative examples include floating dry docks doing routine ship repair, ship scaling, marine cargo checkers and surveyors, marine salvage, and ship dismantling at a floating dry dock.[1]

Three economic models sit inside the code:

• Floating dry docks and routine repair. Vessel owners pay for dock access, labor, materials, inspections, and project management.
• Marine inspection and surveying. Customers pay per inspection, cargo survey, condition report, claim investigation, or compliance assignment.
• Salvage, wreck removal, and end-of-life work. Emergency response, pollution control, ship dismantling, and recycling.

What it explicitly excludes — this matters, because the maritime "support" family is split across several codes:[1]

• 488310 Port and Harbor Operations — running a port, harbor, or canal facility.
• 488320 Marine Cargo Handling — stevedoring and loading/unloading.
• 488330 Navigational Services to Shipping — tug/docking, pilotage, and navigation aids.
• 336611 Ship Building and Repairing — overhauls and repairs performed in a shipyard (most heavy repair lives here, not in 488390).
• 483211 Inland Water Freight Transportation — inland towing and barge transport.
• 237990 dredging, 238320 ship painting, 561720 ship janitorial services, 488510 freight-transportation arrangement (marine agents, customs brokers).

So 488390 is a genuine residual: it captures the inspection, dry-dock repair, emergency-response, and end-of-life segments of shipping, while big-ticket new construction and heavy shipyard repair sit next door in 336611.

Ownership mix. Overwhelmingly private; the federal data do not report ownership by legal form. The surveyor/checker end is a cottage industry of sole proprietors and small partnerships. The capital-intensive end — dry docks, salvage, recycling — is held by family firms (Donjon Marine, T&T), private-equity-backed repair platforms (Vigor), diversified maritime groups (Crowley, Saltchuk/Foss, Moran), strategic industrial owners (EMR Group owns the largest U.S. shipbreaker; HAL Holding owns Boskalis/SMIT), and government-operated facilities that generally fall outside private-business statistics.[18][21][40] Government-owned establishments are largely excluded from the Economic Census.[5]

3. How big it is

Federal data confirm a small, fragmented industry. The core figures below are Histometrics' ingested U.S. Census and SBA statistics.

Those figures imply roughly $333,000 of receipts per employee and average payroll near $82,000 per worker (both mix 2022 receipts with 2023 headcount, so treat as approximate) — consistent with a skilled, technical workforce of surveyors, salvage engineers, riggers, welders, and torch operators.[2][3]

Undercount caveats — read these before treating $2.59 billion as the whole picture:

• Independent surveyors are missed. County Business Patterns counts employer establishments only. A large share of marine surveyors and one-person cargo checkers are nonemployer businesses, so the true count of operators and the true revenue run higher than the employer figures imply.[5]
• Government activity is out of scope. Navigation locks, many canals, the federal reserve fleet, and military/captive repair yards are run or owned by government and do not appear in these business statistics.[5]
• Revenue is lumpy year to year. Salvage and wreck removal are episodic. A single major casualty — the 2024 Baltimore Key Bridge/Dali channel clearance ran about 77 days and drew in multiple national salvors — can swing a given year's receipts, so any one year over- or under-states "normal."[20]
• Heavy repair is elsewhere. Because shipyard repair sits in 336611, 488390 captures only the floating-drydock and non-shipyard slice of the repair economy.[1]

The low HHI (251, well under the 1,500 "unconcentrated" threshold) and modest top-four share point to no dominant national provider — but that average hides a split market (see §8), and a single dry dock or certified emergency-response team can hold strong local pricing power.

4. The investable universe

There is no U.S.-listed pure play whose reporting maps cleanly to NAICS 488390 — because there essentially are none. This is a private industry. The listing below is therefore split into indirect public proxies (in each, 488390-type work is a minor slice of a much larger, differently-driven business) and the private firms that actually do the work.

Indirect public-market exposure (diversified proxies), roughly closest-to-most-indirect:

Treat these as proxies with heavy dilution: the testing-inspection-certification (TIC) majors also straddle general testing/inspection (NAICS 5416), and the marine names bury any 488390-type work inside much larger businesses.

The private operators that actually run the industry:

Salvage, wreck removal, and recycling specialists (the most directly-in-488390 names):

Dry-dock repair and diversified marine-services groups (adjacent, with 488390 arms):

• Vigor Marine Group — private ship-repair/modernization platform; Antin Infrastructure Partners agreed to acquire it (from a Lone Star affiliate), closing expected 2026.[40]
• Bollinger Shipyards — family-owned builder/repairer with dry docks and U.S. government and commercial customers; primarily an adjacent shipyard business.[39]
• Crowley Holdings — family- and employee-owned marine, logistics, energy, and government-services group.[34]
• Saltchuk Resources / Foss Maritime — private family investment platform; Foss provides marine transportation, engineering, and mobile vessel repair.[35]
• Moran Towing / McAllister Towing / Vane Brothers — family-owned marine-services groups (ship-assist, terminal, bunkering, environmental, diving, vessel support); towing itself is 488330/483, but each carries adjacent support work.[36][37][38]

Bottom line for allocators: direct exposure means buying or building a private company; the listed route is a thin, indirect proxy.

5. How the money works

Owners make money in a few distinct ways, and the right yardstick depends on the segment:

• Surveyors and cargo checkers — billable utilization. Asset-light, fee-for-service. Revenue is day rates and per-inspection fees; margins turn on how many hours or jobs each surveyor bills, minus travel. The moat is reputation and accreditation (see §7), which insurers and lenders require. Very low capital intensity — which is exactly why the segment fragments into sole proprietors.[19]

• Floating dry docks and routine repair — throughput. Capital-heavy with real operating leverage: an empty dock still costs money. What matters is dock occupancy, revenue per available dock-day, vessel turnaround and on-time completion, and material-cost pass-through for steel, coatings, parts, and fuel — against fixed costs for the dock and cranes.

• Salvage and wreck removal — episodic upside plus regulated retainers. Two pricing worlds. Emergency salvage often runs on "no cure, no pay" awards under the Lloyd's Open Form (LOF) and its SCOPIC (Special Compensation Protection and Indemnity Clause) cost mechanism: succeed and you earn a share of property value saved; fail and you earn nothing — high variance, high skill premium. Wreck removal and pollution response are usually day-rate or cost-plus. Layered on top is the most attractive economics in the industry: OPA-90 retainer income, where covered shipowners pay recurring annual fees to keep a qualified provider on call — high-margin and scaling with the number of vessels covered (see §7). Operating levers are equipment utilization (cranes, barges, tugs, pumps), crew availability, and casualty frequency. The industry's own shorthand is "feast or famine."[9][10][20]

• Ship recycling — steel tonnage times scrap price. A yard buys an end-of-life vessel, then sells recovered ferrous and nonferrous metal. Profit is recovered tonnage × scrap prices, minus labor and the substantial cost of removing hazardous materials (asbestos, oils, polychlorinated biphenyls). Margins are exposed to the scrap-metal cycle and to how much environmental compliance the market demands.[18]

Common levers across the industry: backlog and contract coverage, emergency-vs-scheduled work mix, customer concentration, cash conversion, and maintenance capital spending. The recurring lesson: utilization and reputation/qualification are the value drivers, and the most durable profits come from the regulatorily mandated retainer stream and steady inspection cadence rather than the headline emergency jobs. The federal data contain no code-level figures for utilization, prices, margins, backlog, or capital spending — those must be analyzed company by company.

6. What drives demand

• Waterborne commerce and vessel traffic. More ships and more cargo mean more surveys, more cargo checks, more routine repair and lighterage. U.S. domestic waterborne traffic totaled about 744.5 million short tons in 2023, spanning petroleum, chemical, agricultural, and industrial flows — the slow structural baseline.[6]
• Fleet maintenance and aging. The U.S. Coast Guard reported 17,765 inspected vessels in 2024; scheduled inspections and dry-dock requirements create recurring demand for repair, surveying, and documentation.[7]
• Marine casualty frequency. Groundings, collisions, container-ship fires, and sinkings drive salvage and wreck removal — unpredictable but very large when they hit (e.g., the 2024 Baltimore bridge collapse).[20]
• Regulatory mandates. OPA-90 salvage-and-firefighting rules turn a portion of demand into a legal requirement that scales with the trading fleet (§7).[9]
• Fleet age and the scrapping cycle. Weak freight rates push owners to retire old ships, feeding recycling yards; strong markets keep ships trading. Scrap-steel prices set recycling economics.[18]
• Safety and environmental compliance. More complex fuel systems, emissions rules, ballast-water controls, and insurer requirements increase inspection and engineering work.
• Government and defense fleets. Navy, Coast Guard, research, and government-operated vessels support demand that private business statistics may not capture; three Brownsville-area yards together capture the large majority of U.S. Navy/MARAD recycling business.[18]
• Offshore and port infrastructure. Offshore energy, subsea cables, offshore wind, coastal-resilience projects, and federal port/shipyard programs create survey, engineering, and repair demand.[17]
• New environmental rules. The IMO Hong Kong Convention (in force 26 June 2025) requires ships flagged by member states to be recycled only at authorized facilities and mandates hazardous-materials inventories — a tailwind for compliant, higher-standard yards.[11][12]

Judgment: maintenance and compliance demand should be more durable than newbuild demand, but the revenue path stays project-based and geographically uneven.

7. Regulation

The regulatory burden is a competitive barrier as much as a cost.

• U.S. Coast Guard (USCG). Oversees vessel safety, casualty investigation, and Vessel Response Plans, and issues guidance on dry-dock examinations and underwater surveys performed in lieu of dry-docking.[13] It also sets the response-time and provider-qualification rules that define the salvage market.
• Oil Pollution Act of 1990 (OPA-90). Passed after the Exxon Valdez spill. Tank vessels and applicable non-tank vessels over 400 gross tons in U.S. waters must pre-identify and contract Salvage and Marine Firefighting (SMFF) providers meeting strict response-time criteria (33 CFR 155.4050). This is the single most important economic feature of the industry: it creates a recurring retainer market and a qualification bar that only a handful of national providers clear — effectively an oligopoly by regulation.[8][9]
• Salvage law. Emergency awards run through frameworks like the Lloyd's Open Form (LOF) and the SCOPIC clause, adjudicated on value saved and effort.[10]
• Maritime Administration (MARAD). Manages the National Defense Reserve Fleet, awards ship-disposal/recycling contracts, administers Jones Act policy (U.S.-built, -owned, -crewed vessels for coastwise trade — which indirectly supports domestic repair and service infrastructure), and funds small-shipyard grants.[16][17][18]
• EPA and the Clean Water Act. Ship-repair and recycling facilities are regulated for industrial stormwater and discharges under the National Pollutant Discharge Elimination System (NPDES).[14]
• OSHA shipyard-employment rules (29 CFR 1915). Cover confined spaces, fire protection, hazardous materials, machinery, and personal protective equipment; shipbreaking is among the most dangerous occupations, so compliance is central.[15]
• International rules. The IMO Hong Kong Convention (in force June 2025) standardizes safe, authorized ship recycling globally, advantaging compliant yards.[11][12]
• Professional accreditation. Marine surveyors are accredited by the Society of Accredited Marine Surveyors (SAMS) and the National Association of Marine Surveyors (NAMS). Voluntary in law but effectively required by insurers and lenders, this is the segment's real license to operate.[19]

Environmental incidents, worker injuries, vessel casualties, or inaccurate survey work can produce losses far beyond a single project's margin.

8. Competitive dynamics and consolidation

Statistically the industry is unconcentrated: the four largest firms hold only 24.7% of receipts, the top eight 37.9%, and the HHI sits at just 251.[3] That average hides a split market:

• The inspection / dry-dock repair / lighterage end is genuinely fragmented — hundreds of small, regional, often single-owner firms competing on price, turnaround, and local relationships. Local markets can still be concentrated around scarce waterfront land, dry-dock size and lifting capacity, USCG/classification approvals, and scarce skilled labor (welders, marine engineers, divers, surveyors).
• The salvage / wreck-removal / OPA-90 end is an oligopoly. Only a few national players — Donjon-SMIT, Resolve Marine, T&T Salvage — can afford the globally pre-positioned equipment, crews, and regulatory qualification the work demands. High barriers keep it that way.[9][10]

Consolidation is real at the capital-intensive end. EMR (UK) has rolled up U.S. ship recycling (International Shipbreaking) plus Gulf-coast barge recycling and invested about $30 million to meet EU/Hong Kong recycling standards; HAL Holding took Boskalis (and its SMIT salvage arm) private in 2022; Moran acquired Bisso Towboat in 2025; Antin agreed to buy the Vigor repair platform; A.P. Møller Holding's Svitzer was taken private and delisted in 2025; and earlier exits (the Ardent salvage joint venture wound down its salvage business around 2020) thinned the field.[18][21][36][40][41] The pattern: strategic and financial buyers gather the capital-heavy, scarce-asset businesses while the surveyor end stays a cottage industry. The best acquisition targets have scarce physical assets, recurring customer relationships, clean environmental records, and a credible workforce pipeline; the main risk is paying for nominal scale without improving utilization or pricing.

9. Risks

• Revenue lumpiness. Salvage is feast-or-famine; a quiet casualty year hits the top line hard, and owners can defer noncritical repair in weak freight markets.[10]
• Liability and safety exposure. Environmental spills, salvage failures, diving/confined-space incidents, and shipbreaking fatalities carry large legal, financial, and reputational risk.[18]
• Regulatory dependence and change. OPA-90 retainer economics underpin the salvage majors; revisions to those rules, coastwise-trade policy, or emissions requirements could reshape the market either way.[9]
• Commodity and freight cycles. Recyclers are exposed to scrap-steel prices; overall demand tracks trade volumes and industrial production.[18]
• Foreign competition in recycling. South Asian yards (Alang, Chittagong) recycle far more cheaply; U.S. yards depend on Navy/MARAD contracts and customers who require higher environmental and labor standards.[18]
• Asset and customer concentration. Dry docks, cranes, barges, and waterfront facilities need heavy upkeep and can suffer costly outages; a single terminal, fleet owner, or government program can be a large share of revenue.
• Labor scarcity and key-person risk. Skilled marine labor is hard to replace, and the surveyor/checker segment is thin-balance-sheet and reputation-dependent, with succession and single-operator risk.[19]
• Technology. Remote inspection, robotics, digital surveys, and condition-based maintenance can erode demand for basic manual work while raising the value of specialized providers.
• Data risk. Federal statistics do not fully capture nonemployers, government operations, or diversified-company segment economics, making market sizing and comparable-company analysis uncertain.[5]

10. How to invest and the outlook

Public-market routes (indirect only). There is no U.S.-listed pure play. Start with exposure, not labels, and separate the buckets:

• Inspection and certification (TIC) — Intertek (LSE: ITRK), Bureau Veritas (Euronext: BVI), SGS (SIX: SGSN), ABL Group (Oslo: ABL).
• Dry-dock and repair — Fincantieri (Euronext: FCT) via Fincantieri Marine Repair; the closest pure repair assets (Bollinger, Vigor) are private.
• Marine transportation with in-house repair — Kirby (NYSE: KEX).
• Marine technology — Kongsberg Maritime (Oslo: KMAR).
• Offshore support vessels — SEACOR Marine (NYSE: SMHI), Tidewater (NYSE: TDW).

In every case, 488390-type work is a small slice of a larger, differently-driven business, so read segment disclosures and estimate the share of revenue actually tied to U.S. vessel support. Compare service businesses on utilization, backlog, labor productivity, cash conversion, leverage, and maintenance capital spending; for valuation, use enterprise value to earnings before interest, taxes, depreciation and amortization (EV/EBITDA), price-to-earnings (P/E), and free-cash-flow yield only after normalizing for project cycles and dock/fleet replacement needs.

Private-market routes (where the assets are). Direct exposure means owning or backing a private operator — a surveying practice, a regional repair/lighterage firm, a salvage company, or a recycling yard — or investing alongside strategic consolidators like EMR and holding companies like HAL, or private-equity platforms like Antin/Vigor. Actionable forms include direct acquisition, buy-and-build platforms, minority stakes in specialized survey firms, equipment leasing, and asset-backed lending against dry docks, cranes, barges, or waterfront property. Underwriting should emphasize permits, location, dock availability, customer concentration, backlog quality, workforce depth, environmental liabilities, insurance, and realistic replacement capital. The salvage/recycling end has real barriers (capital, regulatory qualification, track record); the surveying end is low-capital and buildable but people-dependent.

Outlook (judgment). Expect steady, unspectacular structural demand. Trade volumes, the OPA-90 retainer mandate, and mandatory inspection cadences provide a durable floor; mandated hazardous-materials inventories and the Hong Kong Convention should keep favoring higher-standard U.S. recycling yards and pull naval/MARAD recycling work forward.[11][18] Occasional large casualties will deliver windfall years no one can time. Fragmentation at the inspection end will persist while consolidation continues at the capital-heavy end. This is best understood not as a growth-equity story but as cyclical, mostly-private, infrastructure-adjacent maritime plumbing — defensively useful, regulation-anchored, and reached by most investors only indirectly. Broad "marine exposure" can still disappoint if it is dominated by freight rates, newbuild cycles, or highly leveraged assets.

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Sources

1. U.S. Census Bureau. "2022 NAICS: 488390 Other Support Activities for Water Transportation" (definition, illustrative examples, cross-references to excluded codes). https://www.census.gov/naics/?details=488390&input=488390&year=2022
2. U.S. Census Bureau. "County Business Patterns: 2023" (establishments, employment, payroll for NAICS 488390); Histometrics ingested federal statistics. https://www.census.gov/data/datasets/2023/econ/cbp/2023-cbp.html
3. U.S. Census Bureau. "Economic Census 2022 — Establishment and Firm Size / Concentration Statistics" (firms, receipts, CR4/CR8/CR20/CR50, HHI for NAICS 488390); Histometrics ingested federal statistics. https://data.census.gov/
4. U.S. Small Business Administration. "Table of Small Business Size Standards" (NAICS 488390: $47.0 million), 2023. https://www.sba.gov/document/support-table-size-standards
5. U.S. Census Bureau. "Understanding Industry Classification Systems / Economic Census scope" (nonemployer and government-operation exclusions), 2022. https://www.census.gov/programs-surveys/economic-census/year/2022/guidance/understanding-naics.html
6. U.S. Army Corps of Engineers, Waterborne Commerce Statistics Center. "Waterborne Commerce" (U.S. domestic tonnage, ~744.5 million short tons, 2023). https://www.iwr.usace.army.mil/About/Technical-Centers/WCSC-Waterborne-Commerce-Statistics-Center/WCSC-Waterborne-Commerce/
7. U.S. Coast Guard. "2024 Flag State Control Annual Report" (17,765 inspected vessels), 2025. https://www.news.uscg.mil/maritime-commons/Article/4271996/2024-flag-state-control-annual-report/
8. Donjon-SMIT. "Salvage and Marine Firefighting Regulations (OPA-90 SMFF)," 2025. https://www.donjon-smit.com/about/smff-regulations/
9. Skuld. "US Vessel Response Plans — Salvage and Marine Firefighting Requirements (33 CFR 155.4050)," 2024. https://www.skuld.com/topics/environment/oil-pollution/america/us-vessel-response-plans---salvage-and-marine-firefighting-requirements/
10. Straits Research. "Marine Salvage Services Market" (industry structure, LOF/SCOPIC pricing, leading providers), 2025. https://straitsresearch.com/report/marine-salvage-services-market
11. International Maritime Organization. "New era for ship recycling as Hong Kong Convention enters into force" (26 June 2025). https://www.imo.org/en/mediacentre/pressbriefings/pages/hong-kong-convention-entry-into-force.aspx
12. Bureau Veritas Marine & Offshore. "IMO Hong Kong Convention to Enter Into Force on 26 June 2025" (classification/survey division), 2025. https://marine-offshore.bureauveritas.com/newsroom/imo-hong-kong-convention-enter-force-26-june-2025
13. U.S. Coast Guard. "Navigation and Vessel Inspection Circular No. 01-89, Change 1: Underwater Survey / Dry-Dock Examination Guidance," 2025. https://www.uscg.mil/Portals/0/REFLAG/UWILD_NVIC_01-89CH_%20COMDTPUB_P16700.4.pdf
14. U.S. Environmental Protection Agency. "Industrial Stormwater Fact Sheet Series: Sector R — Ship and Boat Building or Repair Yards" (Clean Water Act / NPDES). https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=P1007BVQ.TXT
15. Occupational Safety and Health Administration. "29 CFR 1915.2 — Shipyard Employment: Scope and Application." https://www.osha.gov/laws-regs/regulations/standardnumber/1915/1915.2
16. Maritime Administration. "Domestic Shipping: The Jones Act," 2026. https://www.maritime.dot.gov/ports/domestic-shipping/domestic-shipping
17. Maritime Administration. "Small Shipyard Grants," 2026. https://www.maritime.dot.gov/grants-finances/small-shipyard-grants
18. Port of Brownsville / EMR Group. "America's Premier Ship Recycling Port" and "International Shipbreaking LLC" (largest U.S. recycler; Navy/MARAD share; ~$30M compliance investment), 2025. https://www.portofbrownsville.com/americas-premier-ship-recycling-port/
19. SkiSafe. "What are NAMS and SAMS Marine Surveyors?" (surveyor accreditation and roles), 2025. https://www.skisafe.com/blog/Entry/10/what-are-nams-and-sams-marine-surveyors
20. Riviera Maritime Media / DredgeWire. "Donjon: top-tier technology and teamwork enabled rapid clearance after boxship collapsed Baltimore bridge" (Key Bridge/Dali salvage, ~77-day channel clearance), 2024. https://dredgewire.com/donjon-top-tier-technology-teamwork-enabled-rapid-clearance-after-boxship-collapsed-baltimore-bridge/
21. SWZ Maritime. "Boskalis to be delisted as of 9 November 2022" (HAL Holding takeover, ~€4.2bn), 2022. https://swzmaritime.nl/news/2022/10/11/boskalis-to-be-delisted-as-of-9-november-2022/
22. Donjon Marine Co., LLC. Company website (salvage, dredging, recycling, ship repair), 2026. https://donjon.com/
23. Resolve Marine Group. "Salvage & Marine Firefighting (OPA-90)," 2026. https://resolvemarine.com/services-capabilities/salvage-marine-firefighting-OPA-90
24. T&T Salvage / T&T Group. Company website (marine salvage and wreck removal), 2026. https://ttgroup-ttsalvage.com/
25. Intertek Group plc. "Investors" and marine/cargo inspection services, 2025–2026. https://www.intertek.com/investors/
26. Bureau Veritas SA. "Investors" (Marine & Offshore division), 2026. https://group.bureauveritas.com/investors
27. SGS SA. "Marine services / cargo inspection," 2026. https://www.sgs.com/en/industries/transportation
28. ABL Group ASA. "Annual Report 2024," 2025. https://abl-group.com/investor-news/abl-group-asa-annual-report-2024/
29. Fincantieri. "Fincantieri Marine Repair," accessed 2026. https://www.fincantieri.com/en/gruppo/societa/controllate-e-collegate/Fincantieri-Marine-Repair
30. Kirby Corporation. "2025 Form 10-K," 2026. https://www.sec.gov/Archives/edgar/data/56047/000119312526054016/kex-20251231.htm
31. Kongsberg Maritime. "Kongsberg Maritime Begins Trading on Oslo Stock Exchange," 2026. https://www.kongsbergmaritime.com/news-and-events/news-archive/2026/kongsberg-maritime-begins-trading-on-oslo-stock-exchange/
32. SEACOR Marine Holdings Inc. "2025 Annual Report," 2026. https://www.sec.gov/Archives/edgar/data/1690334/000119312526159300/d658556dars.pdf
33. Tidewater Inc. "Investor Relations" (offshore support-vessel services), 2026. https://investor.tdw.com/
34. Crowley. "Company Overview," accessed 2026. https://www.crowley.com/company-overview/
35. Foss Maritime / Saltchuk. "About Us," accessed 2026. https://www.foss.com/about-us/
36. Moran Towing. "Moran Towing Corporation Acquires Bisso Towboat," 2025. https://www.morantug.com/news/moran-towing-corporation-acquires-bisso-towboat-strengthening-operations-along/
37. McAllister Towing. "About," accessed 2026. https://www.mcallistertowing.com/about
38. Vane Brothers. "About Us," accessed 2026. https://www.vanebrothers.com/about-us
39. Bollinger Shipyards. "Who We Are," accessed 2026. https://www.bollingershipyards.com/who-we-are/
40. Vigor Marine Group. "Antin to Acquire Vigor Marine Group," 2026. https://www.vigormarine.com/news-press/antin-to-acquire-vigor-marine-group
41. Svitzer / A.P. Møller Holding. "History" (privatization and 2025 delisting), 2026. https://svitzer.com/who-we-are/history/