Dispute Resolution

Disputes challenge both the business and the individuals involved. Significant value, progress, reputation and commercial relationships are often at stake. It is crucial that disputes are handled in a manner that provides predictability, appropriate resource allocation and the best possible foundation for continued operations.

Thommessen assists in all phases of a dispute – from early assessment of risk and options for action, to negotiations, mediation, arbitration and court proceedings. The goal is always a solution that is legally robust, commercially sound, and tailored to the client's needs.

Effective dispute resolution requires structure and good project management. We assemble bespoke teams for each case, combining procedural expertise with relevant legal and industry insight. Through a clear project model and digital tools, we ensure progress, transparency and ongoing oversight of timelines, activities and documentation.

Thommessen has one of Norway's largest and most experienced dispute resolution practices, handling a high number of cases before the courts and in arbitration each year. We regularly appear before the Supreme Court, and several of our lawyers have experience from cases before the EFTA Court and the European Court of Human Rights.

We also have extensive experience with Norwegian and international commercial arbitration, both as counsel and as arbitrators, under rules from the OCC, SCC, DIA, DIS and ICC, among others, as well as ad hoc arbitration, including under the NOMA Rules.

Our services include

Early strategic assessment of disputes and litigation risk
Negotiations, private mediation and court-annexed mediation
Interim injunctions and other urgent matters
Litigation before the courts at all levels
Norwegian and international arbitration (institutional and ad hoc)

Thommessen is extraordinarily focused and pragmatic. Client
Chambers & Partners Europe, 2026

Disputes across practice areas

Disputes often arise where legal, commercial and industry-specific considerations intersect. Thommessen regularly assists in complex cases in the following areas, among others:

Thommessen has one of Norway's largest and most respected employment law departments, with broad experience in employment disputes across industries. We assist in demanding cases such as personnel matters, collective bargaining disputes, workforce adjustments, and pension and entitlement disputes, where both complexity and consequences are often significant for the business and those involved.

Disputes concerning non-compete clauses and the establishment of competing businesses are particularly complex, especially where shareholder relations or intellectual property rights are involved. Such cases require swift and precise handling, and may involve interim court orders with significant commercial implications. We combine specialist employment law expertise with solid experience in corporate law and dispute resolution, providing advice that also addresses commercial, reputational and human considerations. Together with the client, we assemble the right team to ensure effective and prudent handling of the dispute.
Contact persons
- Tron Dalheim
  Partner Advokat (H)
- Trond Hatland
  Partner Advokat (H)
Thommessen assists banks, financial institutions and other participants in the financial industry in complex, high-value disputes. We have in-depth knowledge of key agreements in the banking and finance sector and the regulatory framework, and handle matters including default cases and enforcement of security interests.

In financial disputes, our dispute resolution lawyers work closely with Thommessen's banking and finance department, ensuring an effective combination of specialist legal expertise and deep industry understanding. We handle cases before both courts and arbitral tribunals, combining legal precision with commercial insight to provide strategic advice from early risk assessment to final resolution.
Contact persons
- Henning Harborg
  Partner Advokat (H)
- Nanette Arvesen
  Partner Advokat
The requirements relating to sustainability and business human rights create increased risk of disputes and litigation concerning climate, environment, reporting and supply chain accountability. Businesses face an increasingly complex regulatory landscape and growing pressure from authorities, investors and other stakeholders.

Thommessen assists companies, board members and investors in business-critical ESG-related disputes, including climate-related litigation, greenwashing claims and claims under the Transparency Act. We combine specialist expertise in sustainability and corporate law with solid litigation experience, and provide strategic advice throughout the process from risk assessment and dialogue with authorities to handling disputes before the courts.
Contact persons
- Hedvig Moe
  Partner Advokat
- Nanette Arvesen
  Partner Advokat
Stock exchange and securities regulations impose strict requirements on transparency, disclosure obligations and market conduct for listed companies. Breaches can trigger disputes, sanctions and damages claims, with significant financial and reputational consequences.

Thommessen assists in complex stock exchange and securities disputes, including matters relating to inside information, market abuse, administrative fines and investor claims. We have broad experience with cases before the Financial Supervisory Authority, stock exchange authorities and the courts, and provide strategic advice from early risk assessment and regulatory dialogue to litigation where necessary.
Contact persons
- Nanette Arvesen
  Partner Advokat
- Henning Harborg
  Partner Advokat (H)
Disputes in commercial real estate span a range of legal areas, including financing, contract and lease law, corporate law and planning and building law, often involving both private parties and public authorities. The cases are typically complex and of significant commercial importance.

Thommessen assists in negotiations and disputes concerning commercial real estate, both before the courts and in arbitration. With in-depth industry understanding and solid litigation experience, we provide strategic advice aimed at effective solutions, whether through negotiation or legal proceedings. When the case requires it, we assemble cross-disciplinary teams combining commercial insight and specialist dispute resolution expertise.
Contact persons
- Eirik W. Raanes
  Partner Advokat (H)
- Kristine Hyldmo Bjørnvik
  Partner Advokat
Construction projects in the building, civil engineering, offshore, energy and infrastructure sectors are often technically complex, long-term and capital-intensive. This creates increased risk of disputes, both during project execution and at final account stage.

Thommessen assists in complex construction disputes across industries. We combine in-depth understanding of the specific project with solid litigation experience, and provide strategic advice aimed at effective handling of the conflict. Through close collaboration with the client's key resources, we assemble teams tailored to the case, whether the dispute is resolved through negotiation, arbitration or court proceedings.
Contact persons
- Kristine Hyldmo Bjørnvik
  Partner Advokat
- Svein Aage Valen
  Partner Advokat (H)
In recent years, we have seen an increasing number of financial regulatory disputes as a result of stricter regulation nationally and in the EU/EEA. We provide advice and handle cases concerning regulatory compliance for banks, investment firms, fund managers and other financial actors, often with the state as the opposing party.

We have extensive experience with cases concerning authorisations, licensing requirements, supervision, sanctions and complaints against the Financial Supervisory Authority and other authorities, and have had several cases before the Supreme Court on financial regulatory issues. Our dispute resolution lawyers work closely with our specialist financial regulatory department to ensure comprehensive and effective handling of the dispute.
Contact persons
- Henning Harborg
  Partner Advokat (H)
- Nanette Arvesen
  Partner Advokat
Thommessen has broad experience with disputes in renewable energy and infrastructure, and in-depth knowledge of the regulatory framework and contract types used in such projects. We have a solid understanding of administrative decisions, licence conditions and risk allocation, and assist in all phases of the contractual relationship.

We assist owners, developers, operators and suppliers in disputes relating to renewable energy and infrastructure, including construction disputes and expropriation cases. Through the combination of regulatory insight and litigation experience, we protect the client's interests in both negotiations and legal proceedings.
Contact persons
- Kristine Hyldmo Bjørnvik
  Partner Advokat
- Svein Aage Valen
  Partner Advokat (H)
Insurance disputes require specialist expertise and good knowledge of the market. Thommessen assists both insurance companies and policyholders in all types of insurance cases, from early dialogue to legal resolution.

We have broad experience with disputes concerning insurance contracts, whether resolved through negotiations, before the courts or in arbitration. Several of our lawyers are regularly appointed as arbitrators or mediators in insurance cases, and we also have extensive experience with reinsurance disputes, including the largest cases in this area in Norway in recent years.
Contact persons
- Andreas Meidell
  Partner Advokat, dr. juris
- Henrik Møinichen
  Partner Advokat
Public decisions and regulations can have significant consequences for business operations. Disputes arise at the intersection of businesses' rights and governmental regulation and sanctions, and such cases can be business-critical and of great commercial significance – including questions relating to permits, licences, regulatory frameworks, market access or the right to conduct business.

Thommessen assists business actors in disputes relating to public authorities and business regulation before Norwegian courts and the EFTA Court. We combine in-depth industry knowledge with solid expertise in administrative law and litigation experience, and assist from early dialogue with the authorities to potential court proceedings. We have extensive experience from cases including state aid, procurement, financial regulatory matters, planning and building law as well as licensing and supervisory matters.
Contact persons
- Henning Harborg
  Partner Advokat (H)
- Trond Hatland
  Partner Advokat (H)
Private settlement disputes often raise complex questions about assets, inheritance and generational transition, may involve significant value and are often highly demanding for those involved. Such cases can arise both upon dissolution of marriage and cohabitation, and in connection with estate settlements.

Thommessen assists private individuals in family law disputes, including matters concerning prenuptial agreements, cohabitation agreements, wills and property settlements. Our lawyers have broad experience with mediation, negotiations and litigation before the courts, and combine high professional competence with the necessary understanding of the human aspects of the case. Where needed, we draw on specialist expertise in areas such as tax law, corporate law and valuation to ensure comprehensive and robust solutions.
Contact persons
- Henning Harborg
  Partner Advokat (H)
- Karoline Gloppen
  Managing Associate Advokat
Group litigation is complex and places great demands on legal expertise, strategic assessments and effective process management. Such cases can entail significant financial exposure and extensive documentation and require close liaison with the board, management and supervisory authorities.

Thommessen assists parties in group litigation and has solid experience handling such processes. We assemble teams with the right specialist and litigation expertise, and provide comprehensive and strategic advice through all phases of the case, including in negotiation situations.
Contact persons
- Henning Harborg
  Partner Advokat (H)
- Julie Rasmussen Solli
  Specialist Counsel Advokat
Intellectual property disputes often concern a business's most valuable assets and raise questions about rights to technology, including patents, copyright and trade secrets. Such cases are often technology-intensive and of significant commercial importance.

Thommessen assists in intellectual property disputes by combining legal expertise with close collaboration with technical experts. Our lawyers have long experience working in effective teams of lawyers and technologists, and in quickly and thoroughly familiarising themselves with the client's technology and business. We have assisted in intellectual property cases across a range of key industries, including pharmaceuticals, energy, manufacturing and shipping.
Contact persons
- Eirik W. Raanes
  Partner Advokat (H)
- Camilla Vislie
  Partner Advokat (H)
Thommessen assists in disputes relating to insolvency and restructuring, representing lenders, borrowers, guarantors, creditors and estates, including bank syndicates. We have broad experience with cases concerning voidable transactions, unlawful distributions, disputes between creditor groups, enforcement of security and director liability.

Our lawyers combine legal expertise with commercial understanding, and assist in all phases of insolvency-related disputes - from early conflict management to litigation before the courts. Our dispute resolution lawyers work closely with Thommessen's insolvency and restructuring team to ensure comprehensive and case handling.
Contact persons
- Henning Harborg
  Partner Advokat (H)
- Nanette Arvesen
  Partner Advokat
In commercial disputes involving international parties, arbitration is often chosen as the dispute resolution mechanism. Such cases place particular demands on experience with the arbitration process and the relevant rules, whether the arbitration is conducted ad hoc or under institutional frameworks.

Thommessen has one of Norway's most experienced practices in international commercial arbitration. Our lawyers act as counsel and arbitrators in large and complex cases, both in Norway and internationally. We support the client throughout the process - from strategic assessments and selection of arbitral forum to advocacy and handling of subsequent issues relating to the arbitral award.
Contact persons
- Andreas Meidell
  Partner Advokat, dr. juris
- Henrik Møinichen
  Partner Advokat
Thommessen regularly assists in competition disputes concerning alleged breaches of Norwegian and EU/EEA competition law. Our lawyers represent clients in cases involving review of decisions by the competition authorities and in damages actions arising from competition law infringements.

We have in-depth knowledge of the substantive competition rules and the particular evidentiary issues such cases raise. With experience from proceedings before the Competition Appeals Tribunal, Norwegian courts, the EFTA Court and the EU courts, we handle extensive competition cases through effective and structured processes tailored to each case.
Contact persons
- Eirik W. Raanes
  Partner Advokat (H)
- Siri Teigum
  Partner Advokat (H)
Contract disputes can arise in all types of business relationships and may concern questions about options, price regulation, termination of agreements and claims arising from breach of contract. Such cases are often complex, involve large sums and extensive documentation, and may require particular care where the parties are to continue their collaboration.

Thommessen assists in contract disputes across industries, including some of the largest and most complex cases in recent years. We assemble bespoke teams with relevant specialist expertise and use effective digital tools for structured collaboration and document management throughout the dispute resolution process.
Contact persons
- Henrik Møinichen
  Partner Advokat
- Kristine Hyldmo Bjørnvik
  Partner Advokat
Thommessen assists contracting authorities and tenderers in disputes relating to public procurement, both before the Public Procurement Appeals Board and the courts. We have broad experience with interim injunctions to halt procurement processes, as well as damages claims.

Our experience across sectors and industries provides a strong foundation for effective handling of procurement disputes. Through Thommessen's dispute resolution department and project model, we ensure structured case management, rapid progress in injunction cases and predictable frameworks for clients.
Contact persons
- Eirik W. Raanes
  Partner Advokat (H)
- Wenche Sædal
  Partner Advokat
Offshore projects are often technical, long-term and costly, and disputes can arise both during project execution and in connection with final settlement. Such cases require a good understanding of the specific project and the sector's operating conditions.

Thommessen assists in offshore and oil services disputes, and has extensive experience in finding solutions where possible. When the case must be decided by legal process, we assemble teams with specialist expertise and broad litigation experience for arbitration or the courts, based on in-depth knowledge of the sector and market standards.
Contact persons
- Henrik Møinichen
  Partner Advokat
- Kristine Hyldmo Bjørnvik
  Partner Advokat
Most acquisitions and mergers proceed without problems, but when disagreements arise afterwards, significant value is often at stake and the cases can be complex. Disputes may concern, for example, price adjustments, warranty claims or hidden defects.

Thommessen has assisted both buyers, sellers and insurance companies in post M&A disputes, and we know what it takes to achieve the best possible outcome. We combine in-depth knowledge of the transaction's background with legal and commercial understanding, and provide strategic advice on handling the dispute – whether through negotiations, mediation or before the courts. Our assistance covers both early case assessment and subsequent procedural follow-up.
Contact persons
- Stig Berge
  Partner Advokat (H)
- Nanette Arvesen
  Partner Advokat
Strict requirements for professionalism and due care apply to board members, executive management and professional practitioners such as auditors, lawyers, brokers and accountants. Breaches of these requirements can result in significant liability. The cases are often complex and may be both personally and professionally demanding for those involved.

Thommessen assists clients in professional and director liability cases, both in advance of disputes and as advisers and counsel before the courts. We have broad experience with such cases, including the interplay between liability and liability insurance, and provide structured and effective assistance from early risk assessment and fact-finding to handling the dispute itself.
Contact persons
- Stig Berge
  Partner Advokat (H)
- Nanette Arvesen
  Partner Advokat
Corporate disputes can arise between owners, the board, management and other stakeholders, and may concern shareholder conflicts, interpretation of shareholders' agreements, validity of resolutions by corporate bodies, redemption claims, dividends, investigations or damages liability. Such cases can have major implications for the company's operations and often involve significant value.

Thommessen assists in corporate disputes, from negotiations and mediation to litigation before the courts. We combine specialist legal expertise with understanding of the commercial and human aspects of the conflict, and assemble cross-disciplinary teams tailored to each case.
Contact persons
- Stig Berge
  Partner Advokat (H)
- Nanette Arvesen
  Partner Advokat
Shipping disputes typically arise in contractual relationships or as liability cases following maritime accidents, and may raise questions under both Norwegian and international maritime law. The cases may involve complex jurisdictional and choice of law issues, particularly where parties, vessels, accident location and insurers are connected to different countries.

Thommessen's shipping lawyers assist Norwegian and foreign shipowners, charterers, shipyards and marine insurers in shipping-related disputes through negotiations, before the courts and in arbitration. We have long experience conducting such cases in both Norwegian and English, and several of our lawyers are also appointed as arbitrators in maritime disputes.
Contact persons
- Henrik Møinichen
  Partner Advokat
- Andreas Meidell
  Partner Advokat, dr. juris
Disputes in the seafood industry often arise at the intersection of complex operational conditions, extensive regulation and significant economic value. Effective handling requires in-depth industry knowledge, cross-disciplinary expertise and high responsiveness.

Thommessen assists actors along the entire value chain in fisheries and aquaculture, both nationally and internationally. We have broad experience with commercial and regulatory disputes, and combine industry understanding with strong expertise in corporate law, capital transactions, financing, M&A and dispute resolution.

We assist in disputes concerning equipment, vessels and facilities, including questions about design, functionality, performance, certification, progress and economics. Our experience also covers innovation and development projects, production on land and at sea, as well as processing and sales. Cost-intensive and technically advanced solutions can give rise to demanding conflicts that must be handled swiftly and purposefully.

In regulatory disputes, we assist in cases concerning orders, refusals and interventions in licences and permits, as well as dialogue with authorities. We have particular experience with disputes concerning environmental issues, including vulnerable species, habitat types and other environmental conflicts, and assist both preventively and in formal dispute resolution processes.

Tax and duties also give rise to disputes in the seafood industry. Thommessen assists with strategic advice, appeals handling and dispute resolution, including matters concerning resource rent tax and transfer pricing. Our cross-disciplinary teams combine tax expertise with regulatory insight and in-depth knowledge of the industry.

We also assist in disputes concerning rights and value, including intellectual property, ownership, corporate control, validity of decisions, valuation and investigation, often in the wake of transactions or generational transitions. We also have extensive experience with insurance and damages settlements, including loss quantification.

Contract disputes are resolved through negotiations, arbitration or court proceedings, both in Norway and internationally. Thommessen's project model, digital tools and cross-disciplinary teams provide structured and effective handling, with particular emphasis on protecting operations and reputation. We have broad experience with arbitration and several of our lawyers are appointed as arbitrators.
Contact persons
- Trond Hatland
  Partner Advokat (H)
- Eirik W. Raanes
  Partner Advokat (H)
Disputes concerning tax and duties often involve large amounts and complex factual and economic circumstances. The cases typically raise technically demanding legal questions that must be presented clearly and persuasively to courts without specialist tax expertise. Effective handling of such cases therefore requires cross-disciplinary teams with substantial expertise and litigation experience.

Thommessen has extensive experience assisting taxpayers in disputes against the tax authorities, including in matters of principle before the courts and the Supreme Court. Our lawyers regularly litigate tax and duties cases, and have experience from a broad spectrum of issues, including the participation exemption method, transfer pricing, transaction costs, tax liability for foreign companies and property tax.

We also have significant experience with duties disputes, including VAT, customs duties and excise duties. Over time, the tax authorities' focus on the duties area has increased, leading to a significant number of cases before the courts. Thommessen has litigated several key duties cases and developed particular expertise in this area.

Tax and duties cases often raise issues that cut across legal areas, for example financial regulatory, corporate law or international matters. Thommessen's broad commercial law expertise makes it possible to assemble teams that handle all relevant aspects of the case in a comprehensive and credible manner.

We assist taxpayers throughout the process, from administrative notices and appeals handling to full court review. When a dispute arises, we stand by the taxpayer's side all the way, with the aim of securing the best possible outcome.
Contact persons
- Finn Backer-Grøndahl
  Partner Advokat (H)
- Bjørn Christian Lilletvedt Tovsen
  Partner Advokat (H)
Disputes concerning technology and IT contracts typically arise in connection with the development, purchase or outsourcing of IT services, and often concern questions about progress, collaboration, scope of work, functionality or delivery. Such conflicts can have major consequences for business operations.

Thommessen assists in technology and IT contract disputes, and has long experience in finding solutions where possible. When the dispute must be resolved by legal process, we assemble teams with specialist expertise and broad litigation experience for arbitration or the courts, based on in-depth understanding of technology, projects and market standards.
Contact persons
- Eirik W. Raanes
  Partner Advokat (H)
- Henning Harborg
  Partner Advokat (H)
Businesses may be subject to scrutiny, investigation and sanctions from the National Authority for Investigation and Prosecution of Economic and Environmental Crime (Økokrim) and other authorities, whether as a result of specific suspicions or routine supervision. Such cases can have serious criminal, financial and reputational consequences.

Thommessen has extensive experience assisting clients in cases concerning corporate criminal liability, during investigation and in the event of charges against individuals, as well as in cases where businesses have been subject to sanctions from competition, financial or labour inspectorates and other sector authorities. We often assist from the outset during raids, searches, arrests and interviews, and protect the client's rights throughout the process.

Regulatory intervention often raises parallel issues, including matters concerning access to documents, seizure, employment law, data protection, stock exchange reporting and the board's handling of the matter. Subsequently, we assist with fact-finding and review of material, including seized documentation, using effective analysis and project tools.

Where there are grounds to contest sanctions, we assist in all phases of the dispute, from assessment of litigation risk to advocacy before the courts. Cases are handled through our established project model, which provides structure and predictability for the client.

Economic crime cases are often based on underlying civil law issues in areas such as tax, securities law, competition law and employment law. Thommessen has both the necessary breadth and criminal law expertise to handle such cases, and assembles teams with relevant specialist and industry experience. We also have significant experience with disputes arising in the wake of economic crime cases and regulatory investigations.
Contact persons
- Henning Harborg
  Partner Advokat (H)
- Karoline Gloppen
  Managing Associate Advokat