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Karen is a partner in our Disputes and Investigations team.  She has 20 years’ experience acting for domestic and international clients in high stakes commercial litigation, contentious regulatory matters and investigations. Her experience extends across a broad range of commercial disputes, including shareholder/investor claims, financial services disputes, contractual claims including breach of warranty/indemnity claims, challenges arising from EU law and constitutional law, and cross-border/multi-jurisdictional litigation.  Karen regularly advises clients in relation to contentious regulatory disputes and corporate crime matters, including in relation to internal investigations, reporting to law enforcement, fraud, corporate offences, and anti-bribery and corruption compliance under Irish and EU regimes.

Karen leads our multi-practice Regulatory Investigations practice.  She regularly advises boards and senior management in all aspects of their regulatory engagement, communications with stakeholders, reputational risk, to secure optimum outcomes.  She is an advocate of alternative dispute resolution and has negotiated positive settlements to secure confidential resolutions for clients in many cases.

Experience and Education

Karen’s experience includes advising:

  • an international fintech in highly publicised commercial court proceedings, including in relation to obtaining a non-reporting order and search and seizure orders, and its claims in relation to conspiracy, defamation, and corporate espionage;
  • an investment fund management company in connection with civil claims arising from alleged breaches of duty of care and duty to act in the best interests of investors in connection with a fraudulent investment manager and loss of investments;
  • an investment holding company in connection with precedent setting Commercial Court proceedings arising from a shareholder dispute, and subsequent appeals to the Court of Appeal and Supreme Court;
  • an energy company in connection with an EU law and constitutional law challenge, including referral to the CJEU;
  • a global alternative asset management firm in successfully defending vexatious injunctive proceedings to restrain completion of a multi-million euro property acquisition
  • an alternative investment fund manager in relation to the first Central Bank administrative sanction procedure under the new procedure in connection with contraventions of the European Union (Alternative Investment Fund Managers) Regulations 2013 (the AIFM Regulations);
  • a major multinational technology company and gatekeeper in relation to compliance with the Digital Markets Act;
  • a family office in successfully defending commercial court proceedings arising from an alleged joint venture option arrangement relating to a private investment in flagship commercial property assets
  • a global investment firm in connection with injunction proceedings to restrain a competitor from completing a transaction in violation of contractual terms
  • an asset management company in relation to Commercial Court proceedings regarding a dispute with an employee in relation to an incentives scheme various financial institutions in regulatory investigations and enforcement proceedings;
  • boards and senior executives in relation to their duties and obligations to the company and regulator in connection with regulatory investigations and commercial litigation against the company;
  • a regulated firm in relation to a large-scale remediation project, and a Central Bank investigation and enforcement action;
  • a global payment technology solutions company in connection with a dispute arising from a joint venture arrangement with a financial institution;
  • an international financial institution in relation to long running Commercial Court proceedings arising out of the fraud of Bernard L Madoff Investment Securities;
  • an asset management company in relation to Commercial Court proceedings regarding the management of certain funds;
  • a number of clients across various industry sectors with regards to warranty and indemnity claims under acquisition contracts;
  • a number of clients who have been the victim of cyber-attacks, including in respect of their regulatory engagement and litigation management post-incident an international pharma company in relation to proceedings arising from a dispute in relation to the interpretation of a share option agreement and ancillary contractual arrangements;
  • clients across a number of industry sectors on potential fraud, bribery and corruption offences and reporting obligations under section 19 of the Criminal Justice Act 2011
  • a private investment company in relation to its hostile takeover and restructuring of an international oil and gas exploration company headquartered in Dublin; and
  • a group of companies in the construction industry, including in relation to cross border issues, security, enforcement, recognition of judgments and insolvency measures, and, an appeal to the Supreme Court.
  • University College Dublin, BCL
  • Trinity College Dublin, LLM

News and Insights

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Matheson advises Carne Group on major strategic investment by leading private equity investor, Permira, at EUR1.4bn valuation

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Accolades

“Karen Reynolds is the best in the country at what she does, and is the first person I would call when I need a steer.”

Disputes Resolution: The European Legal 500

2026

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