Simon Airey focuses his practice on global, cross-border and internal investigations, financial and regulatory crime, bribery and corruption, money laundering, tax and fraud inquiries, data breaches, dawn raids, asset tracing, international enforcement and corporate compliance issues. Simon serves as co-head of McDermott Will & Schulte’s global investigations and compliance practice.

He has conducted a wide range of investigations and corporate defence assignments in different sectors, including construction, defence, financial services, gambling, oil and gas, logistics, pharmaceuticals and telecommunications. Simon represents both companies and individuals in criminal and regulatory proceedings and in associated litigation.

Simon advises a large number of multinational groups on their global compliance programs and assists clients with corporate risk assessments and pre- and post- M&A due diligence. He conducts tailored training for boards and senior management and has lectured around the world on a range of topics including the UK Bribery Act and the UK Criminal Finances Act. He advises a number of organisations on the corporate criminal offence of failing to prevent the facilitation of tax evasion and served on the UK Law Society committee which devised related guidance for the legal profession.

In addition to leading various major tax, fraud and bribery investigations, Simon has recently defended multi-party litigation in relation to a significant data breach in the UK, dealt with an FCA investigation relating to a global payment services provider and represented a high-profile individual in relation to a multi-million pound D&O insurance dispute in the context of a US DoJ prosecution. He has also advised a foreign government in relation to various tax and transparency issues and represented over 50 financial institutions served with data production orders by HM Revenue & Customs in the UK.

Leigh-Alexandra Basha focuses her practice on domestic and international tax and estate planning. She counsels an affluent international client base on a wide range of sophisticated matters, including estate and trust administration, family wealth preservation, foreign trust planning, tax compliance, as well as business succession, expatriation, and pre-immigration planning. Leigh is head of the firm’s Washington, DC, Private Client Practice Group.

Leigh was an adjunct professor of wills, trusts and estates at American University Washington College of Law. She lectures and has written extensively about international tax and estate planning issues, and is editor of A Guide to International Estate Planning: Drafting, Compliance, and Administration Strategies, Second Edition.

Raminta Dereskeviciute focuses her practice on product compliance, trade regulation (sanctions and export controls) and ESG. She has significant experience in advising on EU and UK chemical legislation (REACH), product safety and liability rules and frequently represents clients before the European Chemicals Agency Board of Appeal. Raminta also advises businesses on the implications Brexit has in relation to a range of regulatory compliance issues.

Raminta counsels clients on the EU and the UK sanctions regimes and export controls, including in higher risk jurisdictions such as Russia and Iran. Her experience covers the review and design of compliance programs, including giving training to client teams on controlled goods, prohibited jurisdictions, persons and activities. Raminta assists companies in liaising with regulators when assessing whether their activities are in breach of EU or UK sanctions regimes, or whether authorisations / licenses from the national authorities are appropriate. Raminta has participated as a chair and speaker on sanctions related panels at the Cambridge International Symposium on Economic Crime.

Raminta has a peerless grasp of EU chemicals, metals and mining policy, including conflict minerals legislation and the issues surrounding ethical supply chain management for these industries. She also advises companies and trade associations on the European Commission’s Chemical Strategy for Sustainability, building upon her long standing experience on legislative developments in the field of chemicals (REACH, CLP, GHS, WFD, Seveso III, RoHS, WEEE and others).  Raminta devises compliance and crisis management programs and assists global industrial products manufacturers with international product recalls. Raminta featured  in Chemical Watch, Bloomberg Environment and numerous other publications discussing EU chemicals and environmental policy, industry compliance and Member State enforcement as well as implications that Brexit will have on various stakeholders. She is a contributor to the most comprehensive book published on REACH, “Best Practice Guide to Regulation (EC) No 1907/2006”, by Beck/Hart.

Romain Desmonts focuses his practice on tax advice to French and multinational companies, with an emphasis on the tax aspects of domestic and cross-border mergers, acquisitions, and group restructurings, as well as indirect tax matters.

Romain also regularly provides tax advice to high net-worth individuals on domestic and international estate planning issues, especially in a US-France context.

He has developed a strong background in tax controversy and litigation for corporate and private clients.

Stéphane Dionnet is co-head of McDermott’s Antitrust Mergers Focus Group and has over 20 years of experience practicing international competition law, and has experience liaising with competition authorities in the European Union, United States and Asia. Stéphane has advised global corporations on how to navigate complex multijurisdictional merger control matters. He has represented clients in numerous cartel investigations and has also successfully assisted companies in obtaining conditional immunity from the European Commission and other competition law agencies in and outside the European Union.

Stéphane has experience across a wide range of sectors including consumer products, energy, entertainment, financial services, technology, pharmaceuticals, retail, e-commerce and telecommunications.

Stéphane is recognized by Lexology Index as a Recommended Lawyer in Competition (2025) and is listed in Global Competition Review’s GCR 100 (2025). He is also recommended by The Legal 500 EMEA for Competition for 2023–2024. Clients describe Stéphane as “an excellent competition lawyer with a great strategic sensibility” and praise him as being “great to work with,” noting his “fantastic work product.”

Earlier in his career, Stéphane worked for three years within the “Merger Network” of the European Commission’s Directorate-General for Competition. He was case-handler in high-profile transactions, including phases 1 and 2 with remedies.

Lisa Göransson focuses her practice on advising leading corporates, private equity firms, and financial institutions on complex cross-border M&A and joint ventures across the Nordic region and globally.

Lisa is a dual qualified English and Swedish lawyer with close to 30 years of corporate law experience with leading law firms in both London and Stockholm.

She has also held General Counsel roles, including with a Swedish Nasdaq listed multinational company, and served as an acting judge with the Stockholm Court of Appeals.

Annette Keller advises clients on international tax law, tax audits as well as tax litigation before tax courts and the German Supreme Tax Court (Bundesfinanzhof), tax structuring, group reorganizations and group tax law.

As a licensed tax specialist (Fachanwalt für Steuerrecht) she is a regular author and speaker on tax issues, in particular at conferences on international tax law.

She is an officer of the Taxes Committee of the International Bar Association.

Jessica Lee represents states, corporates, and individuals in complex cross-border and high-value commercial disputes, with a particular focus on civil fraud and asset recovery actions, company and shareholder disputes, and technology and blockchain related litigation.

She has acted on some of the most significant civil fraud matters in recent years, frequently advising on freezing, proprietary, and disclosure injunctions. Jess has substantial experience in the execution of search orders and delivery up orders. Her strong focus on technology disputes includes acting on crypto asset recovery matters and advising on contentious matters arising from crypto exchange insolvencies and decentralised finance protocols. She has also advised on significant investigations and compliance matters, including investigations by the US Department of Justice and the Serious Fraud Office.

Jess serves on the board of the Crypto Fraud and Asset Recovery network (CFAAR), is co-editor of the GLP Cryptoassets Law Over Borders Comparative Guide, and contributed to the UK Jurisdictional Taskforce Legal Statement on Digital Securities. Prior to joining McDermott Will & Schulte, Jessica was a partner in the London office of a leading international law firm.

Hilton Mervis has nearly 30 years’ experience of litigating and resolving high-value, complex and multi-jurisdictional disputes. He represents corporations, private equity firms, hedge funds and high-net-worth individuals on a wide variety of disputes and has particular experience in the alternative investment sector, covering private equity and hedge fund litigation, partnership disputes, complex civil fraud, contractual and banking disputes, shareholder and corporate governance disputes, and financial services matters.

Hilton is a solicitor advocate and member of the Commercial Court Users Committee by appointment. He is a founding member and Chair of the London Commercial Litigators’ Forum. He is also the editor of the authoritative text Managing Private Fund Disputes (PEI Media) and of Global Legal Post’s Commercial Litigation Guide.

Kristina Nordlander has a leading EU antitrust, litigation, and regulatory practice, with a particular focus on technology and life sciences. She advises clients on complex EU competition law matters, including antitrust investigations, merger control, regulatory challenges, and litigation before the European Commission and the EU courts.

With more than two decades of experience, Kristina is known for her deep understanding of how EU institutions operate and for her strategic use of EU law tools to address competition and market access issues. Her practice focuses on competition law enforcement matters affecting the digital single market, online selling, mobile and electronic payments, app stores, antitrust aspects of AI and other technology-driven sectors. She regularly advises online marketplaces and digital platforms on EU antitrust compliance and on new regulatory regimes, including the EU Digital Markets Act.

Kristina has extensive experience of litigating alleged antitrust violations, market access disputes, product classifications and restrictions, data protection and transparency issues, and legal privilege matters. She also has significant expertise in EU state aid law, particularly in relation to tax.

She has worked in London, Brussels, and New York and is widely recognised as a thought leader in EU competition law.

Sebastian Orozco advises high-net-worth individuals, families, and fiduciaries on sophisticated US and cross-border estate, gift, and income tax matters. His practice encompasses international estate planning, foreign and domestic trust planning, structuring US and foreign investments, wealth preservation, and U.S. tax compliance. 

Sebastian has particular experience with preimmigration and expatriation planning. He counsels clients on trust classification and distribution issues, restructuring strategies involving gifts, grantor and nongrantor trusts, and cross-border holdings, and expatriation tax consequences. He also assists US beneficiaries and families with foreign trusts, foreign estates, reporting obligations, and the tax-efficient transfer of wealth across generations and borders. 

Sebastian writes and speaks on cross-border private client planning, pre-immigration and expatriation. Prior to McDermott, he served as a judicial law clerk at the US Tax Court. He earned an LL.M. in Taxation with honors from Georgetown University. 

Represents private equity funds, banks, real estate companies, and REITs in a wide range of real estate transactions

Advises lenders and borrowers on mortgage and mezzanine loan financing and preferred equity transactions

Counsels clients on the purchase, workout, and restructuring of troubled loans

Represents domestic and international sellers and purchasers in the purchase, sale, sale-leaseback, and financing of commercial properties across asset classes

Michael Silva focuses his practice on international tax law, with an emphasis on US investment structures, cross-border transactions, tax treaty planning and US activities of foreign banks. He has significant experience forming investment funds and advising family offices. Michael currently serves as head of the Miami Tax practice and co-head of the Latin America practice.

Michael also advises Brazilian and Asian investors on investments in US real estate projects, and assists multinational corporations on establishing a business presence in the United States.

Maintaining an active private client practice, Michael regularly advises families on trusts and private trusts companies and other techniques to transfer wealth and business assets. Michael advises foreign clients on the US income, estate and gift tax consequences of alternative inbound investment structures while utilizing income, estate and gift tax treaties to minimize tax and regulatory burdens. He coordinates the formation of foreign trusts, corporations and advises clients the US reporting requirements imposed on foreign trusts with US beneficiaries. Michael also assists international banks and trustees on dealing with US clients.

Michael represents financial institutions, insurers, broker-dealers, custodians, funds, fund advisers and managers, trust companies and other financial intermediaries in connection with the requisite protocols and procedures to validate compliance with FATCA requirements.

Michael is board-certified by the Florida Bar in Tax Law and in International Law, and is a Certified Public Accountant. Michael previously served as adjunct professor of Law in the University of Miami Law School Graduate Tax Program.

Designs, amends, and administers pension, profit sharing, 401(k), employee stock ownership, and 403(b) plans, as well as nonqualified deferred compensation arrangements

Counsels plan fiduciaries on ERISA Title I matters, including investment policies, private equity, hedge funds, and other alternative investments

Advises multinational clients on global employee benefits and compliance issues

Represents clients before the IRS, Department of Labor, and PBGC on benefit plan audits, corrections, and plan terminations

Handles complex, global criminal and civil matters, including internal investigations, and investigations conducted by the Department of Justice

Focuses on healthcare enforcement and compliance, including False Claims Act, Anti-Kickback Statute, and Stark Law matters

Represents clients in antitrust criminal investigations and related class actions, and advises on global compliance programs

Has extensive experience with Japanese clients, including in global investigations and implementation and updating of global compliance programs

Brings extensive appellate experience, having served as lead appellate counsel in more than 100 cases in nearly all of the US courts of appeals and before the US Supreme Court

Handles pro bono litigation projects in a wide array of substantive areas, including civil rights, LGBTQ+ rights, children’s rights, disabilities’ rights, and immigration as the firm’s pro bono litigation partner