HELIX ENERGY SOLUTIONS GROUP INC (HLX) Business

Item 1. Business

OVERVIEW

Helix Energy Solutions Group, Inc. (together with its subsidiaries, unless context requires otherwise, “Helix,” the “Company,” “we,” “us” or “our”) was incorporated in 1979 and in 1983 was re-incorporated in the state of Minnesota. We are an international offshore energy services company that provides specialty services to the offshore energy industry, with a focus on well intervention, robotics and decommissioning operations. Our services are key in supporting a global energy transition by maximizing production of existing oil and gas reserves, decommissioning end-of-life oil and gas fields and supporting renewable energy developments. See “Our Operations” below for additional information regarding business operations.

Our principal executive offices are located at 3505 West Sam Houston Parkway North, Suite 400, Houston, Texas 77043; our phone number is 281-618-0400. Our common stock trades on the New York Stock Exchange (“NYSE”) under the ticker symbol “HLX.” Our Chief Executive Officer submitted the annual CEO certification to the NYSE in May 2025 as required under its Listed Company Manual. Our principal executive officer and our principal financial officer have made the certifications required under Section 302 of the Sarbanes-Oxley Act, which are included as exhibits to this Annual Report.

Please refer to the subsection “Certain Definitions” on page 14 for definitions of additional terms commonly used in this Annual Report. Unless otherwise indicated, any reference to Notes herein refers to Notes to Consolidated Financial Statements in Item 8. Financial Statements and Supplementary Data of this Annual Report.

OUR OPERATIONS

We provide a range of services to the oil and gas and renewable energy markets primarily in the Gulf of America (deepwater and shelf), Brazil, North Sea, West Africa and Asia Pacific regions. Our services are segregated into four reportable business segments: Well Intervention, Robotics, Shallow Water Abandonment and Production Facilities.

Services we currently offer to the offshore oil and gas market worldwide include:

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Services we currently offer to the offshore renewable energy market worldwide include:

Well Intervention

Our Well Intervention segment provides services enabling our customers to safely access subsea offshore wells for the purpose of performing production enhancement or decommissioning operations, thereby mitigating the need to drill new wells by extending the useful lives of existing wells and preserving the environment by preventing uncontrolled releases of oil and natural gas. Our Well Intervention segment provides services primarily in the Gulf of America, Brazil, North Sea, Asia Pacific and West Africa regions.

We engineer, manage and conduct well intervention operations, which include production enhancement and abandonment, and construction operations in water depths ranging from 100 to 10,000 feet. As major and independent oil and gas companies develop deepwater reserves, we expect the number of subsea trees to increase, which can improve long-term demand for well intervention services. Drilling rigs historically have been and still are used in subsea well intervention. Our purpose-built well intervention vessels derive competitive advantages in the development and management of subsea reservoirs from their lower operating costs, with an ability to mobilize quickly and to maximize operational time by more efficiently performing a broad range of tasks related to intervention, construction and IRM services.

Our well intervention vessels include the Q4000, the Q5000, the Q7000, the Seawell, the Well Enhancer, and two chartered vessels, the Sea Helix 1 (formerly Siem Helix 1) and the Siem Helix 2. Our well intervention equipment includes 12 intervention systems consisting of eight intervention riser systems (“IRSs”), three subsea intervention lubricators (“SILs”) and the Riserless Open-water Abandonment Module (“ROAM”), some of which we provide on a stand-alone basis.

In the Gulf of America, we operate the Q4000 and Q5000 riser-based semi-submersible well intervention vessels. The Q4000 has served customers in the spot market in the Gulf of America since 2002 and notably served as a key emergency response vessel in the Macondo well control and containment efforts in 2010. The Q5000 has operated in the Gulf of America since 2015.

In Brazil, we provide well intervention services with the Sea Helix 1 and Siem Helix 2 monohull riser-based well intervention vessels under long-term charter from Sea1 Offshore (formerly Siem Offshore). The Sea Helix 1 commenced operations in April 2017 and is under contract with Petrobras through at least November 2028. The Siem Helix 2 commenced operations in December 2017 and is under contract with Petrobras through at least January 2028.

In the North Sea, we operate the Seawell and Well Enhancer monohull light well intervention vessels. The Seawell has provided well intervention and abandonment services since 1987. The vessel underwent major capital upgrades in 2015 to extend its estimated useful economic life by approximately 15 years. The Well Enhancer has performed well intervention, abandonment and CT services since it joined our fleet in 2009.

The Q7000 semi-submersible riser-based well intervention vessel commenced operations in January 2020, operates globally with projects conducted in Nigeria, New Zealand and Australia, and is currently performing well intervention work offshore Brazil.

Our Subsea Services Alliance with SLB leverages the parties’ capabilities to provide a unique, fully integrated offering to clients, combining marine support with well access and control technologies. Through our collaboration, we and SLB jointly developed a 15K IRS and the ROAM.

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Robotics

Our Robotics segment provides trenching, seabed clearance, offshore construction and IRM services to both the oil and gas and the renewable energy markets globally, thereby assisting the delivery of renewable energy and supporting responsible energy transition. Additionally, our robotics services are used in and complement our well intervention services. Our Robotics segment includes 39 work-class ROVs, six trenchers, three IROV boulder grabs, and robotics support vessels chartered on long-term, short-term, flexible and spot bases to facilitate our ROV and trenching operations. We offer our ROVs, trenchers and IROV boulder grabs on a stand-alone basis or on an integrated basis with chartered robotics support vessels.

Our robotics business operates globally, with primary operations in the North Sea, the Gulf of America, Asia Pacific, Brazil and West Africa regions. As global marine construction activity levels increase and as the complexity and water depths of the facilities increase, the scope of robotics services has expanded. Our chartered vessels enable us to offer an integrated package to our customers including marine access, ROV services, project management and engineering services. Our robotics assets and experience allow us to meet the technological challenges of our customers’ subsea activities worldwide.

Over the last decade and especially in recent years there has been an increase in offshore activity associated with the growing renewable energy market. As the level of activity for offshore renewable energy projects, including wind farm projects, has increased, so has the need for reliable services and related equipment. We provide cable burial services related to subsea power cable installations as well as seabed clearance and site preparation services around the world using our chartered vessels, trenchers, ROVs and IROV boulder grabs. In 2025, revenues derived from offshore renewable energy contracts accounted for 49% of our global Robotics segment revenues. We believe that over the long term our robotics business is positioned to continue providing services to a range of clients in the renewable energy market.

Shallow Water Abandonment

Our Shallow Water Abandonment segment provides services in support of the upstream and midstream ‎industries predominantly in the Gulf of America shelf, including offshore oilfield decommissioning and ‎reclamation, well intervention, IRM, heavy lift and commercial diving services. Our Shallow Water Abandonment segment includes Helix Alliance that was acquired in July 2022, a vertically integrated company that offers a diversified fleet of marine assets including nine liftboats, six offshore supply vessels (“OSVs”), three dive support vessels (“DSVs”), a heavy lift derrick barge, a crew boat, 20 P&A systems and six CT systems.

Production Facilities

Our Production Facilities segment includes the HP I, the HFRS and our ownership of mature oil and gas properties. All of our current Production Facilities activities are located in the Gulf of America.

The HP I, a ship-shaped dynamically positioned floating production vessel capable of processing up to 45,000 barrels of oil and 80 million cubic feet of natural gas per day, has been under contract to the Phoenix field operator since February 2013 and is currently under an agreement through at least June 1, 2027.

We developed the HFRS in 2011 as a culmination of our experience as a responder in the 2010 Macondo well control and containment efforts. The HFRS combines our capabilities with certain well control equipment that can be deployed to respond to a well control incident. We are under agreement through March 31, 2027 with various operators to provide access to the HFRS for well control purposes.

Our Production Facilities segment also includes acquired mature deepwater offshore wells and related subsea infrastructure.

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GEOGRAPHIC AREAS

We primarily operate in the Gulf of America (deepwater and shelf), Brazil, North Sea, West Africa and Asia Pacific regions. Our North Sea operations and our Gulf of America shelf operations are usually subject to seasonal changes in demand, which generally peak in the summer months and decline in the winter months. See Note 14 for disclosures regarding revenues and property and equipment by geographic location.

CUSTOMERS

Our customers consist primarily of major, national and independent oil and gas producers and suppliers, pipeline transmission companies, renewable energy companies and offshore engineering and construction firms. The level of services required by any particular customer depends, in part, on the size of that customer’s budget in a particular year. Consequently, the level of revenues from a particular customer may be significant in one year but not significant in other years. The percentages of consolidated revenues from major customers (those representing 10% or more of our consolidated revenues) are as follows: 2025 — Shell (18%) and Petrobras (10%); 2024 — Shell (12%) and Talos (12%); and 2023 — Apache (11%) and Shell (10%). We provided services to over 80 customers in 2025.

COMPETITORS

The oilfield services and renewables services markets are highly competitive. Price and the ability to access specialized vessels, systems and other equipment, attract and retain skilled personnel, and operate safely are important factors to competing in these markets. Our principal competitors in well intervention are international drilling contractors and also include AKOFS Offshore, Baker Hughes, C-Innovation, Expro, Oceaneering, TechnipFMC, Trendsetter and Well-Safe Solutions. Our principal competitors in the robotics business include Asso Divers, Atlantic Marine, Briggs Marine, C-Innovation, DeepOcean, DOF Subsea, Fugro, James Fisher, Oceaneering and UTROV. Our principal competitors in shallow water abandonment include Aries Marine, C-Dive, Cardinal Services, Chet Morrison, Crescent Energy Services, Laredo Offshore Services, Manson Gulf, Offshore Liftboats, Offshore Marine Contractors, Seacor, Shore Offshore, Supreme Energy, Turnkey Offshore Project Services and White Fleet. Our competitors may have more or differing financial, personnel, technological and other resources available to them.

SUSTAINABILITY

Our vision as a preeminent offshore energy transition company is supported by our sustainability priorities of People, Governance, Health and Safety, Value Creation, Environmental Impact, and Ethics. Sustainability initiatives and disclosures are embedded in these business values and priorities with a top-down approach led by management and our Board of Directors (our “Board”). Each Committee of our Board oversees elements designed to support these priorities. Specifically, as a stated responsibility of its charter, our Board’s Corporate Governance and Nominating Committee (the “Governance Committee”) oversees, assesses and reviews the disclosure and reporting of any sustainability matters impacting the Company’s business and industry, including with respect to climate change. Sustainability is reviewed on an ongoing basis in conjunction with environmental, health and safety, and social matters at each Governance Committee meeting. Our Board’s Audit Committee (the “Audit Committee”) oversees Helix’s compliance program, enterprise risk management processes, including business continuity, and cybersecurity risk and prevention management. Lastly, our Board’s Compensation Committee (the “Compensation Committee”) oversees executive management performance and compensation, including sustainability key performance indicators and human capital management.

While the Board and its committees oversee strategic sustainability initiatives with respect to Helix’s strategy surrounding biodiversity and climate change, our Climate Change Action Committee, comprised of key leaders from Quality, Health, Safety, Environmental (“QHSE”), finance, legal, our business units and management, evaluates Helix’s impact on climate change, implements our go-forward strategies and assists in providing comprehensive disclosures. Our expectations and goals align with the underlying belief that fossil fuels will not be eliminated from consumption, but rather there will be a gradual global transition from relying primarily on fossil fuels to a more balanced approach that includes renewable energy, such as wind farms and other alternative fuels.

We emphasize continual improvement by establishing goals to improve our safety record and increase transparency for our stakeholders. Our services facilitate both extending the value and therefore the life cycle of underutilized wells, which in turn mitigates the need to drill new wells and the responsible transition to additional energy sources. These efforts are described in greater detail on our Corporate Sustainability Platform available at www.helixesg.com/sustainability.

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HUMAN CAPITAL MANAGEMENT

As of December 31, 2025, we had 2,212 employees. Of our total employees, we had 441 employees covered by collective bargaining agreements or similar arrangements. We consider our overall relationships with our employees, suppliers and vendors to be satisfactory. Further, we expect all employees to maintain a work environment free from harassment, discrimination and abuse, and one where employees treat each other with respect, dignity and courtesy. These tenets are further described in our Human Rights Policy and our Supplier and Vendor Expectations, both of which are available on our website at www.helixesg.com/about-helix/our-company/ethics-and-compliance.

Employee Health and Safety

Our corporate vision of a zero-incident workplace is based on the belief that all incidents are preventable and that we manage our working conditions to eliminate unsafe behavior. We have established a corporate culture in which QHSE takes priority over our other business objectives. Everyone at Helix has the authority and the duty to “STOP WORK” they believe is unsafe. Helix management actively encourages critical safety behaviors to avoid injuries to people, environmental disturbances and damage to assets through Hazard Hunts, Behavioral Best Safety Standards, and employee consultations, among other initiatives. Our Health, Safety and Security Statement and Environmental and Energy Statement of Policy are available on our website, located at www.helixesg.com/about-helix/our-company/safety. Our QHSE management systems and training programs were developed based on common industry work practices, and by employees with on-site experience who understand the risk and physical challenges of the offshore work environment. Certain management systems of our business units have been independently assessed and registered compliant with ISO 9000 (Quality Management Systems), ISO 14001 (Environmental Management Systems), and ISO 45001 (Occupational Health and Safety Management Systems).

We undertake to regularly and properly train our staff to be as prepared as possible to perform our operations safely. Our staff receives updated and relevant training required for their jobs, and Helix leadership actively engages staff so that behaviors reflect the training and a critical safety approach. Each vessel and shore-based employee is assigned a Qualifications and Training Matrix that specifies qualifications and training required of the employee. Training is tracked and evaluated for quality assurance. Ongoing and thoughtful employee participation is a vital element in the success of our QHSE processes. While we believe in the strength and effectiveness of our QHSE programs, we continuously review how we can improve our control of QHSE risks through our employees’ behavior and feedback.

Attraction and Retention of Talent

We are committed to attracting and retaining high-performing employees through our diverse talent base and evaluating and promoting throughout our organization based on skills and performance. We seek the best candidates without regard to factors such as race, religion, color, national origin, age, sex, gender, sexual orientation, gender identity, disability, marital status, veteran status, genetic information, socioeconomic background or any other basis that would be in violation of any applicable federal, state, local or international law. We are committed to diversity and inclusion throughout our workforce, and believe that employing people with different backgrounds, experiences and perspectives makes Helix a stronger company. In 2025, our worldwide workforce represented 40 different nationalities. We track tenure and voluntary employee turnover and use this data to inform our human capital management strategy. As of December 31, 2025, our global voluntary annual turnover rate was 13%. Further, our Board defines diversity expansively and has determined that it is desirable to have diverse viewpoints, professional experiences, backgrounds and skills on our Board, with the principal qualification of a director being the ability to act effectively on behalf of Company shareholders. Our Board has remained diverse following a long-standing refreshment process. Relevant information regarding our talent attraction and retention can be found in the Talent Management section of our Corporate Sustainability Platform available at www.helixesg.com/sustainability/people-communities#talent-management.

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Human Rights, Anti-Slavery and Anti-Human Trafficking

We are committed to respecting and protecting human rights everywhere we operate and expect similar standards of suppliers, vendors and partners, including requiring periodic assessments and audits to confirm there is no modern slavery, human trafficking or underage employees in our supply chains or in any part of our business. Our workplace policies and procedures demonstrate our commitment to acting ethically and with integrity in our business relationships, and to implementing and enforcing effective systems and controls to prevent slavery and human trafficking from taking place anywhere in our supply chains. We provide periodic Anti-Human Trafficking training for employees to further arm our workforce with the tools to identify and prevent human trafficking. Our Modern Slavery Statement is available on our website, located at www.helixesg.com/modern-slavery-statement and our Statement on Human Rights, as approved by the Board of Directors is available on our website at www.helixesg.com/about-helix/our-company/ethics-and-compliance.

GOVERNMENT REGULATION

Overview

We provide services primarily in the Gulf of America (deepwater and shelf), Brazil, North Sea, West Africa and Asia Pacific regions, and as such we are subject to numerous laws and regulations, including international treaties, flag state requirements, environmental laws and regulations, requirements for obtaining operating and navigation licenses, local content requirements, and other national, state and local laws and regulations in force in the jurisdictions in which our vessels and other assets operate or are registered, all of which can significantly affect the ownership and operation of our vessels and other assets. We operate mature offshore oil and gas wells, some of which are producing and which ultimately we plan to decommission. Being an owner and operator of wells subjects us to additional regulatory oversight from the Bureau of Ocean Energy Management (“BOEM”) and the Bureau of Safety and Environmental Enforcement (“BSEE”).

International Conventions

Our vessels are subject to applicable international maritime convention requirements, which include, but are not limited to, the International Convention for the Prevention of Pollution from Ships (“MARPOL”), the International Convention on Civil Liability for Oil Pollution Damage of 1969, the International Convention on Civil Liability for Bunker Oil Pollution Damage of 2001 (ratified in 2008), the International Convention for the Safety of Life at Sea of 1974 (“SOLAS”), the International Safety Management Code for the Safe Operation of Ships and for Pollution Prevention (the “ISM Code”), the Code for the Construction and Equipment of Mobile Offshore Drilling Units (the “MODU Code”), and the International Convention for the Control and Management of Ships’ Ballast Water and Sediments (the “BWM Convention”). These regimes are applicable in most countries where we operate; however, the vessel’s flag state and the country where we operate may impose additional requirements, including as described below. In addition, these conventions impose liability for certain environmental discharges, including strict liability in some cases.

U.S. Overview

In the U.S., we are subject to the jurisdiction of the U.S. Coast Guard (the “Coast Guard”), the U.S. Environmental Protection Agency (the “EPA”) as well as state environmental protection agencies for those jurisdictions in which we operate, three divisions of the U.S. Department of the Interior (BOEM, BSEE and the Office of Natural Resources Revenue), and the U.S. Customs and Border Protection (the “CBP”), as well as classification societies such as the American Bureau of Shipping (the “ABS”). We are also subject to the requirements of the federal Occupational Safety and Health Act and comparable state laws that regulate the protection of employee health and safety for our land-based operations.

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International Overview

We provide services globally and accordingly can be subject to local laws and regulations wherever we operate. Those laws and regulations generally govern environmental, labor, health and safety and other matters. The regulatory regimes of the U.K. and Brazil are of particular importance given the locations of our current operations. The U.K. Continental Shelf in the North Sea is regulated by the North Sea Transition Authority (the “NSTA”) in accordance with the Petroleum Act 1998. The NSTA controls the Petroleum Operations Notices with which we comply for various well intervention and subsea construction projects, as required. The NSTA also regulates the environmental requirements for our operations in the North Sea. We are subject to the Oil Pollution Prevention and Control Regulations 2005. In the North Sea, international regulations govern working hours and the working environment, as well as standards for diving procedures, equipment and diver health.

Our operations in Brazil are predominantly regulated by the Brazilian National Agency of Petroleum, Natural Gas and Biofuels, the federal government agency responsible for the regulation of the oil sector. Additional regulatory oversight is provided, among others, by the Brazilian Institute of the Environment and Renewable Natural Resources, which oversees Brazilian environmental legislation, implements the National Environmental Policy and exercises control and supervision of the use of natural resources, the Brazilian Health Regulatory Agency, which regulates products and services subject to health regulations, the Ministry of Labor, which regulates a variety of subjects related to employment and other work permitting matters, and the Brazilian Navy, which regulates maritime operations.

Operating Certification

Each of our vessels is subject to regulatory requirements of the country in which the vessel is registered, also known as the flag state. In addition, the country in which a vessel is operating may have its own requirements with respect to safety and environmental protections. These requirements must be satisfied in order for the vessel to operate. Flag state requirements are largely established by international treaties such as MARPOL, SOLAS, the ISM Code and the MODU Code, and in some instances, specific requirements of the flag state. These include engineering, safety, safe manning and other requirements related to the maritime industry. Each of our vessels is subject to a “class” status with a classification society, with respect to whether the vessel has been built and maintained in accordance with the rules of the classification society and complies with applicable flag state rules and international conventions. Our vessels generally undergo a class survey once every five years. In the U.S., the Coast Guard sets safety standards and is authorized to investigate marine incidents, recommend safety standards, and inspect vessels at will. We are also bound by manning requirements implemented by the Coast Guard for operations on the U.S. Outer Continental Shelf (“OCS”).

Local Content Requirements and Cabotage Rules

We are subject to local content requirements with respect to vessels, equipment and crews utilized in certain of our operations. Governments in some countries, notably in Australia, Brazil and in the West Africa region, establish and enforce such requirements along with other aspects of the energy industries in their respective countries.

A number of jurisdictions where we operate require that certain work may only be performed by vessels built and/or registered in that jurisdiction. In some instances, an exemption may be available, or we may be subject to an additional tax to use a non-local vessel. In the U.S., we are subject to the Merchant Marine Act of 1920 (commonly referred to as the “Jones Act”), which generally provides that only vessels built in the U.S., owned at least 75% by U.S. citizens, and crewed by U.S. citizen seafarers may transport merchandise between points in the U.S. The Jones Act has been applied to offshore oil and gas and wind farm work in the U.S. through interpretations by the CBP.

Offshore Energy Regulation

Our business is affected by laws and regulations as well as changing tax laws and policies relating to the offshore energy industry in general. The operation of oil and gas properties located on the OCS is regulated primarily by BOEM and BSEE. Among other requirements, BOEM may require lessees of OCS properties to post bonds or provide other adequate financial assurance in connection with the P&A of wells located offshore and the removal of production facilities. As an owner and operator of wells located on the OCS, we maintain a BSEE-approved Oil Spill Response Plan. BSEE also oversees requirements relating to well control equipment utilized during intervention and decommissioning operations. As a provider of well control equipment, we are subject to these regulations for operation, maintenance and surface and subsea testing of our equipment during intervention and decommissioning operations.

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Other Regulatory Impact

Additional proposals and proceedings before various international, federal and state regulatory agencies and courts could affect the energy industry, including curtailing production and demand for fossil fuels.

ENVIRONMENTAL REGULATION

Overview

Our operations are subject to a variety of national (including federal, state and local) and international laws and regulations governing the discharge of materials into the environment or otherwise relating to environmental protection. Numerous governmental departments issue rules and regulations to implement and enforce these laws that are often complex, costly to comply with, and carry substantial administrative, civil and possibly criminal penalties for compliance failure. Under these laws and regulations, we may be liable for remediation or removal costs, damages, civil, criminal and administrative penalties and other costs associated with releases of hazardous materials (including oil) into the environment, and that liability may be imposed on us even if the acts that resulted in the releases were in compliance with all applicable laws at the time those acts were performed. Some of the environmental laws and regulations applicable to our business operations are discussed below, but this discussion does not cover all environmental laws and regulations that govern or otherwise affect our operations.

MARPOL

The U.S. is one of approximately 175 member countries party to the International Maritime Organization (“IMO”), an agency of the United Nations responsible for developing measures to improve the safety and security of international shipping and to prevent marine pollution from ships. The IMO negotiated MARPOL, which imposes on the shipping industry environmental standards relating to oil spills, management of garbage, the handling and disposal of noxious liquids, harmful substances in packaged forms, sewage, and air emissions.

OPA

The Oil Pollution Act of 1990, as amended (“OPA”), imposes a variety of requirements on offshore facility owners or operators in the U.S., and the lessee or permittee of the U.S. area in which an offshore facility is located, as well as owners and operators of vessels. Any of these entities or persons can be “responsible parties” which are strictly liable for removal costs and damages arising from facility and vessel oil spills or threatened spills. Failure to comply with OPA may result in the assessment of civil, administrative and criminal penalties. In addition, OPA requires owners and operators of vessels over 300 gross tons to provide the Coast Guard with evidence of financial responsibility to cover the cost of cleaning up oil spills from those vessels. A number of foreign jurisdictions also require us to present satisfactory evidence of financial responsibility. We address these requirements through appropriate insurance coverage.

Water Pollution

For operations in the U.S., the Clean Water Act imposes controls on the discharge of pollutants into the navigable waters of the U.S. and imposes potential liability for the costs of remediating releases of petroleum and other substances. Permits may be obtained to discharge certain types of pollutants into state and federal waters. The EPA issues Vessel General Permits (“VGPs”) covering discharges incidental to normal vessel operations, including ballast water, and implements various training, inspection, monitoring, recordkeeping and reporting requirements, as well as corrective actions upon identification of each deficiency. Additionally, certain state regulations and VGPs prohibit the discharge of produced waters and sand, drilling fluids, drill cuttings and certain other substances related to the exploration for, and production of, oil and natural gas into certain coastal and offshore waters. Many states have laws analogous to the Clean Water Act and also require remediation of releases of hazardous substances in state waters. Internationally, the BWM Convention covers mandatory ballast water exchange requirements.

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Air Pollution and Emissions

A variety of regulatory requirements, proposals and legislative initiatives focused on restricting the emissions of carbon dioxide, methane and other greenhouse gases apply to the jurisdictions in which we operate. Annex VI of MARPOL addresses air emissions, including emissions of sulfur and nitrous oxide, and requires the use of low sulfur fuels worldwide in both auxiliary and main propulsion diesel engines on vessels. Directives designed to reduce the emission of nitrogen oxides and sulfur oxides have been issued, and can impact both the fuel and engines that may be used onboard vessels.

CERCLA

The Comprehensive Environmental Response, Compensation, and Liability Act (“CERCLA”) requires the remediation of releases of hazardous substances into the environment in the U.S. and imposes liability, without regard to fault or the legality of the original conduct, on certain classes of persons, including owners and operators of contaminated sites where the release occurred and those companies that transport, dispose of or arrange for the disposal of, hazardous substances released at the sites.

OCSLA

The Outer Continental Shelf Lands Act, as amended (“OCSLA”), provides the U.S. government with broad authority to impose environmental protection requirements applicable to lessees and permittees operating in the OCS. Specific design and operational standards may apply to OCS vessels, rigs, platforms, vehicles and structures. Violations can result in substantial civil and criminal penalties, as well as potential court injunctions that could curtail operations and cancel leases.

Current Compliance and Potential Impact

We believe we are in compliance in all material respects with applicable environmental laws and regulations. We maintain a robust operational compliance program, and we maintain and update our programs to meet or exceed applicable regulatory requirements.

See Item 1A. Risk Factors for further information related to governmental and regulatory requirements affecting our business.

INSURANCE MATTERS

Our businesses involve a high degree of operational risk. Hazards such as vessels sinking, grounding, colliding and sustaining damage from severe weather conditions and operational hazards such as rigging failures, human error, or accidents are inherent in marine operations. These hazards can cause marine and subsea operational equipment failures resulting in personal injury or loss of life, severe damage to and destruction of property and equipment, pollution or environmental damage and the suspension of operations. Damages arising from such occurrences may result in claims that could be significant.

As discussed below, we maintain insurance policies to cover some of our risk of loss associated with our business. We maintain amounts of insurance we believe prudent based on estimated loss potential. However, not all of our business activities can be insured at the levels we desire because of either limited market availability or unfavorable economics.

Our current insurance programs generally cover a 12-month period beginning July 1 each year.

We maintain Hull and Increased Value insurance, which provides coverage for physical damage up to an agreed amount for each vessel. We also carry Protection and Indemnity insurance, which covers liabilities arising from the operation of vessels, and General Liability insurance, which covers liabilities arising from general operations. Onshore employees are covered by Workers’ Compensation, and offshore employees and marine crews are covered by a Maritime Employers Liability (“MEL”) insurance policy, which covers Jones Act exposures. We maintain Operator Extra Expense coverage that provides certain coverage per each loss occurrence for a well control issue on oil and gas properties where we are the operator. In addition to these liability policies, we currently carry various layers of Umbrella Liability in excess of primary limits as well as OPA insurance for our offshore oil and gas properties.

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We customarily have agreements with our customers and vendors in which each contracting party is responsible for its respective personnel. Under these agreements we are typically indemnified against third-party claims related to the injury or death of our customers’ or vendors’ personnel, and vice versa. With respect to well work contracted to us, the customer is typically contractually responsible for pollution emanating from the well. We separately maintain additional coverage designed to cover us under certain circumstances against any such third-party claims associated with well control events.

We also are often required by customers to enter into surety bond arrangements or to post standby letters of credit in favor of the customer. Such surety bond arrangements and letters of credit are designed to protect customers against our failure to perform obligations under customer contracts. The terms of such surety bond arrangements or standby letters of credit vary but are generally consistent with industry practice for such agreements.

We receive Workers’ Compensation, MEL and other insurance claims in the normal course of business. We analyze each claim for its validity, potential exposure and estimated ultimate liability. Our services are provided in hazardous environments where events involving catastrophic damage or loss of life could occur, and claims arising from such an event may result in our being named as a responsible party. We maintain insurance protection that we believe is adequate for our business operations.

WEBSITE AND OTHER AVAILABLE INFORMATION

We maintain a website on the Internet with the address of www.helixesg.com. Copies of this Annual Report for the year ended December 31, 2025, previous and subsequent copies of our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, and any amendments thereto, are or will be available free of charge at our website as soon as reasonably practicable after they are filed with, or furnished to, the SEC. We make our website content available for informational purposes only. Information contained on our website is not part of this report and should not be relied upon for investment purposes. Please note that prior to March 6, 2006, the name of the Company was Cal Dive International, Inc. We satisfy the requirement under Item 5.05 of Form 8-K to disclose any amendments to our Code of Business Conduct and Ethics and our Code of Ethics for Chief Executive Officer and Senior Financial Officers and any waiver from any provision of those codes by posting that information in the Investor Relations section of our website at www.helixesg.com.

The SEC maintains an Internet website at www.sec.gov that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC, including us.

CERTAIN DEFINITIONS

Defined below are certain terms helpful to understanding our business that are located throughout this Annual Report:

Artificial Intelligence (AI):  An engineered system that analyzes large data sets to independently generate content, predictions, or decisions intended to achieve specific objectives and influence operations.

Bureau of Ocean Energy Management (BOEM):  BOEM is responsible for managing environmentally and economically responsible development of U.S. offshore resources. Its functions include offshore leasing, resource evaluation, review and administration of oil and gas exploration and development plans, renewable energy development, National Environmental Policy Act analysis and environmental studies.

Bureau of Safety and Environmental Enforcement (BSEE):  BSEE is responsible for safety and environmental oversight of U.S. offshore oil and gas operations, including permitting and inspections of offshore oil and gas operations. Its functions include the development and enforcement of safety and environmental regulations, permitting offshore exploration, development and production, inspections, offshore regulatory programs, oil spill response and newly formed training and environmental compliance programs.

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Coiled tubing (CT) system:  A continuous length of steel tubing (CT), typically between 1” and 3.25” in diameter, wound onto a large reel together with an injector head, control console, power supply and well control stack. The CT is run inside a well’s production tubing primarily for debris cleanout, pumping fluids or fishing operations though there are numerous other applications.

Decommissioning:  The process of plugging and abandoning oil and gas wells and removing all associated infrastructure (pipelines, platforms, etc.). This is the final stage of oil and gas operations and typically occurs when all of the associated wells have reached the end of their useful production lives.

Deepwater:  Water depths exceeding 1,000 feet.

Dynamic Positioning (DP):  Computer directed thruster systems that use satellite-based positioning and other positioning technologies to provide the proper counteraction to wind, current and wave forces enabling a vessel to maintain its position without the use of anchors.

DP2:  Two DP systems on a single vessel providing the redundancy that allows the vessel to maintain position even in the absence of one DP system.

DP3:  DP control system comprising a triple-redundant controller unit and three identical operator stations. The system is designed to withstand fire or flood in any one compartment. Loss of position should not occur from any single failure.

Dive support vessel (DSV):  A vessel used as a floating base for commercial diving projects, with the basic requirements to keep station accurately and reliably throughout the diving operation.

Heavy lift derrick barge:  A vessel with a crane capacity to lift large, heavy objects, primarily used for installation or removal of large offshore structures. Lifting capacities typically range from 500 to over 2,000 tons, compared to construction vessels which generally have less than 250 ton lifting capacity.

Intervention Riser System (IRS):  A subsea system that establishes a direct connection from a well intervention vessel, through a rigid riser, to a conventional or horizontal subsea tree in depths up to 10,000 feet. An IRS can be utilized for wireline intervention, production logging, CT operations, well stimulation, and full P&A operations, and provides well control in order to safely access the well bore for these activities.

Intervention system:  A subsea system that establishes a direct connection from a well intervention vessel to a subsea well in order to provide well control to safely access the well bore for well intervention activities. Intervention systems include Intervention Riser Systems (IRSs), Subsea Intervention Lubricators (SILs) and the Riserless Open-water Abandonment Module (ROAM).

I-plough trencher:  A pre-lay plough spread with the capability to perform boulder clearance, pre-cut trenching and backfill services once the cable, umbilical or pipeline has been laid.

IROV boulder grab:  A subsea grab tool with the capability to perform boulder clearance and debris removal.

Liftboat:  A self-propelled offshore vessel with moveable legs capable of elevating its hull above the surface of the sea to create a stable working platform as opposed to a floating vessel. These vessels are equipped with living quarters, open deck space and at least one crane for lifting operations.

Offshore support vessel (OSV):  A specially designed vessel for the logistical servicing of offshore platforms and subsea installations.

Plug and Abandonment (P&A):  P&A operations usually consist of placing several cement plugs in the well bore to isolate the reservoir and other fluid-bearing formations when a well reaches the end of its lifetime.

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Table of Contents

P&A system:  A set of surface equipment, typically consisting of wireline, pumps, cement blenders and tanks, that is used for placement of mechanical and/or cement plugs in the well bore to P&A a well.

QHSE:  Quality, Health, Safety and Environmental programs designed to protect the environment, safeguard employee health and avoid injuries.

Remotely Operated Vehicle (ROV):  A robotic vehicle used to complement, support and increase the efficiency of diving and subsea operations and for tasks beyond the capability of manned diving operations. ROV also includes ROVDrill, a seabed-based geotechnical investigation system deployed with an ROV system capable of taking cores from the seafloor in water depths up to 6,500 feet.

Riserless Open-water Abandonment Module (ROAM):  A subsea system designed to act as a barrier to the environment during upper abandonment operations and during production tubing removal in open water, when run as a complement to an IRS. ROAM provides the ability to capture contaminants or gas within the system and circulate them back to the safe handling systems on board the vessel, such that no well contaminants are released into the environment.

Saturation diving:  Divers working from special chambers for extended periods at a pressure equivalent to the pressure at the work site, generally required for work in water depths between 200 and 1,000 feet.

Shallow water:  Generally, water depths less than 1,000 feet, including the Gulf of America shelf.

Site clearance:  Activities utilizing ROVs for the safe removal of obstructions, such as boulders, unexploded ordnance (UXOs) and debris, that would inhibit the construction of an offshore wind farm.

Spot vessels:  Vessels not owned or under term charters but contracted on a short-term basis typically to perform specific projects.

Subsea Intervention Lubricator (SIL):  A riserless subsea system designed to provide access to the well bore while providing well control safety for activities that do not require a riser conduit. A SIL can be utilized for wireline, logging, light perforating, zone isolation, plug setting and removal, and decommissioning, and it facilitates access to subsea wells from a vessel to provide safe, efficient and cost effective riserless well intervention and abandonment solutions.

Trencher or trencher system:  A subsea robotics system capable of providing post-lay trenching, inspection, burial and maintenance of submarine cables, flowlines and umbilicals in water depths of 30 to 7,200 feet across a range of seabed and environmental conditions.

Well intervention services:  Activities related to well maintenance and production management and enhancement services. Our well intervention operations include the utilization of slickline and electric line services, pumping services, specialized tooling and CT services.

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