Kevin Cummings is the partner-in-charge of the Firm’s UK Tax Practice.
Kevin is a senior, solutions-driven tax practitioner, having served as a tax partner from within both the legal sector and the Big Four – a hybrid background that enables Kevin to draw upon the strengths of both professions in delivering client advice.
- Advised US groups on European and UK inbound investment.
- Advised UK and US groups on international expansion and group structuring.
- Advised multinationals on efficient group structuring, profit repatriation and tax-free reorganizations, including in relation to permanent establishment taxation arising from computer servers and new, post-pandemic working patterns.
- Legal 500 UK, Recommended, 2023-2025
- Chambers UK, Tax, 2023-2025
- Alternative Investment Management Tax Committee
- Alternative Credit Council Tax Committee
- HMRC and HM Treasury Working Groups, including on debt and derivative taxation reform, cryptoasset taxation, securitization and fund management
- College of Law, JD
- University of Cambridge, LLM
- Utrecht University
- England and Wales
- Englisch
- Französisch
- Deutsch

Dr. Christian Marzlin
Dr. Christian Marzlin berät deutsche und internationale Mandanten bei nationalen und grenzüberschreitenden M&A-Transaktionen.
Christian Marzlin hat langjährige und umfassende Erfahrung im Zusammenhang mit Private Equity, Venture Capital und strategischen Beteiligungen. Darüber hinaus umfasst seine Beratungstätigkeit komplexe strategische Joint-Ventures, Reorganisationen und allgemeine gesellschaftsrechtliche Fragestellungen.
Christian Marzlin berät Mandanten aus verschiedenen Wirtschaftssektoren und hat insbesondere vertiefte Branchenkenntnisse in den Bereichen Medien und Technologie, Gesundheitswesen, Banken und Finanzdienstleistungen, Industrie sowie Konsumgüter.
Vor seinem Eintritt bei McDermott war Christian Marzlin für eine renommierte internationale Sozietät am Standort Frankfurt am Main tätig.
Christian Marzlin beriet:
- Süd Beteiligungen beim Verkauf ihrer Anteile an der KKL-Gruppe an die Triton-Portfoliogesellschaft bluu unit
- myneva Group, ein Portfoliounternehmen von Summa Equity, beim Erwerb der Kuidado GmbH
- Investcorp beim Verkauf von Contentserv an Centric Software
- Handelsblatt/Best Lawyers™, „Ones to Watch“ in Deutschland: Gesellschaftsrecht und Fusionen und Übernahmen, 2023-2025
- Wissenschaftliche Vereinigung für Unternehmens- und Gesellschaftsrecht (VGR)
- Deutsch-Amerikanische Juristen-Vereinigung (DAJV)
- Hanseatisches Oberlandesgericht Hamburg, Zweites Staatsexamen
- Rheinische Friedrich-Wilhelms-Universität Bonn, Dr. jur.
- Rheinische Friedrich-Wilhelms-Universität Bonn, Erstes Staatsexamen
- Deutschland
- Deutsch
- Englisch

Princess Fuller
Princess Fuller focuses her practice on both mergers & acquisitions and private equity transactions across a variety of industries. Princess also advises on energy and infrastructure matters including representing clients on the development, structuring and negotiation of complex project financing transactions and negotiating credit, security and purchase agreements on behalf of sponsors, developers and lenders.
- Represented a solar and storage developer in connection with tax equity investments in its distributed generation portfolios of commercial-scale and community solar projects being developed throughout the United States
- Advised an investment fund in its sale of a healthcare lending platform for approximately $100 million
- Advised the Clermont Group on its investment into Post Era, Inc.
- Best Lawyers: Ones to Watch in America, Energy Law, Mergers and Acquisitions Law, Project Finance Law, 2026
- National Black Lawyers, Top 40 Under 40 (New York), 2019 to 2023
- Super Lawyers, Rising Stars 2024 – Top rated Mergers & Acquisitions attorney in New York, New York
- New York City Bar, African Affairs Committee, board member
- Georgetown University Law Center, JD
- Georgetown University, BS
- Georgia
- New York
- Englisch
- Spanish

Andrew B. Lehman
Andrew (Andy) B. Lehman advises clients in complex mergers and acquisitions, joint ventures, structured equity transactions and management equity arrangements. He represents clients in an array of industries, including conventional and renewable energy, information technology, healthcare, manufacturing, consumer products and financial and business services.
- Represented a public company acquirer in three separate stock-for-stock mergers involving an aggregate transaction value in excess of $2 billion*
- Represented a global private equity group in its buyout of another financial sponsor’s equity interest in a chemicals distribution and storage concern and related joint venture arrangement*
- Advised a financial sponsor in connection with multiple structured equity investments, including its $750 million preferred equity investment in an acquisition vehicle created to acquire oil and gas assets and subsequent recapitalization of the investee company and its $500 million growth investment in a midstream enterprise*
- The Best Lawyers in America, Corporate Law, 2023-2024
- The University of Texas School of Law, JD, cum laude
- University of Chicago, MA, magna cum laude
- Vanderbilt University, BA
- Texas
- Englisch
- Spanish

Mary R. Waller
Mary Waller represents private equity firms and their platform companies, as well as health systems, clinical practices, and other health industry clients, in a variety of transactions and regulatory matters. She advises healthcare clients through the full lifecycle of complex transactions, including mergers and acquisitions, private equity investments and divestitures, management and professional service arrangements, corporate reorganizations and joint ventures. She has advised on physician practice management and ASC transactions in several specialized areas, including urology, cardiology, and dentistry.
Mary offers nuanced, actionable regulatory advice to clients as they navigate compliance issues, including facility licensing, reimbursement, and corporate practice of medicine laws, as well as other legal, regulatory, and business issues that impact healthcare providers.
- Fellowships at Auschwitz for the Study of Professional Ethics, Steering Committee
- American Health Lawyers Association, Member
- Illinois Association of Healthcare Attorneys, Mentorship Committee
- The Cara Collective, Executive Council Member
- University of Michigan Law School, JD, summa cum laude
- University of Southern California, BA
- Illinois
- Englisch
- Spanish

Ming Lei
Ming Lei advises clients on domestic and international merger, divestitures and acquisitions, joint venture, private equity investments, project finance and development and complex commercial contracts in all aspects of the energy and infrastructure business, including marine terminalling and storage, oil and gas exploration, oilfield services, midstream pipeline, refinery and petrochemical and renewable and energy transition.
Pipelines and Other Midstream Business
- Represented Stonepeak Infrastructure Partners in its $3.6+ billion acquisition of substantially all of the assets of Oryx Southern Delaware Holdings LLC and Oryx Delaware Holdings LLC, which comprises of, among others, crude oil gathering and transportation system with approximately 1,200 miles of in-service and under-construction pipeline that across the core of the Delaware Basin*
- Represented Ridgemont Equity Partners in its joint venture investment with Denham Capital Management and the Ontario Power Generation Inc. Pension Plan to back WhiteWater Midstream, MPLX LP and West Texas Gas, Inc. to provide natural gas liquids takeaway capacity from MPLX and WTG gas processing plants in the Permian Basin to the natural gas liquids fractionation hub in Sweeny, TX*
- Represented UBS Investment Bank, as financial advisor to NuStar Energy, in its $1.5+ billion acquisition of Navigator Energy Services, LLC which owns crude oil transportation, pipeline gathering and storage assets in the Midland Basin*
- The Best Lawyers: Ones to Watch in America, Energy Law, 2023-2024
- Legal 500, Industry Focus: Energy Transactions: Oil and Gas, 2021
- Institute for Energy Law (IEL) Leadership Class, 2022 to present
- Asian American Bar Association of Houston, Corporate Counsel Committee, co-chair, 2020 to 2021
- Duke University School of Law, JD
- Wuhan University, BA
- Texas
- China
- New York
- Englisch
- Chinese (Mandarin)

Min Lee
Min Lee counsels private fund clients in connection with the formation and operation of private investment funds as well as the legal, regulatory and compliance issues faced by their sponsors. He has experience serving as legal counsel to numerous institutional and boutique sponsors across a spectrum of investment strategies, including buyout, real estate, credit, growth equity and venture capital, co-investment, fund-of-funds, and secondaries. He also represents clients in connection with the formation of managed accounts, funds-of-one, joint ventures, and other bespoke investment vehicles and products.
- Duke University School of Law, JD
- Yale University, BA
- New York

Kevin Brophy
Kevin Brophy focuses his practice on energy related matters, including the upstream and midstream sectors. He regularly advises on investments in and financings of energy projects and assets, including, mergers, joint ventures and acquisitions and dispositions of assets and equity of energy companies. He has extensive experience preparing and negotiating purchase and sale agreements (asset and equity), joint venture agreements, joint operating agreements, partnership agreements, limited liability company agreements, employment and consulting agreements, credit and security agreements and other agreements and contracts related to the energy industry.
- EIV Capital, LLC in its equity commitment to Penrose Midstream Partners, LLC, a growth-oriented midstream company focused on acquiring, developing, operating and optimizing midstream infrastructure.
- EIV Capital, LLC in the $160 million sale by its portfolio company, Woodland Midstream Partners II, LLC, of natural gas gathering and processing assets in the Permian Basin to DCP Midstream, LP.
- EOG Resources in its acquisition of oil and gas properties in the Utica Shale.
- Kayne Anderson Capital Advisors, L.P. in a $117 million equity commitment by certain of its affiliates to Allegro Mineral Resources, LLC to acquire mineral/royalty interests.
- Legal 500 US, Recommended, 2023-2024
- Houston Business Journal Outstanding Solo Counsel and Up-and-Comer, finalist, 2009
- American Bar Association, member
- State Bar of Texas, member
- Houston Bar Association, member
- University of Florida, LLM
- South Texas College of Law Houston, JD
- Louisiana State University, BS
- Texas
Nick Paul
Nick Paul focuses his practice on employee benefits and executive compensation matters for public and private companies. Nick regularly leads due diligence and advises on employee benefits and executive compensation issues in connection with corporate transactions involving both public and private companies. Nick also regularly drafts and advises on issues related to cash bonus plans, equity compensation plans, phantom unit plans, executive severance and change in control agreements and executive employment agreements.
- Best Lawyers: Ones to Watch in America, Employee Benefits (ERISA) Law, 2025-2026
- University of Southern California Gould School of Law, JD
- Loyola University Chicago, BBA, cum laude
- Illinois
- Wisconsin

Debbie Green
Debbie Green focuses her practice on commercial litigation. She represents clients in litigation matters in certain key areas, such as bankruptcy contested matters, appeals, insurance coverage and bad faith, Telephone Consumer Protection Act (TCPA) class actions, antitrust, and general commercial litigation.
- Represented secured lender in bankruptcy proceedings challenging its exercise of its Article 9 remedies in debtor’s deposit accounts in its possession, including appeal.*
- Represented debtor, which operates community of skilled residential nursing facilities and assisted living facilities, in appeal of favorable decision in dispute with landlord over timeliness of its assumption of leases.*
- Mentor, Big Brothers Big Sisters of America
- Member, Children’s Advocacy Center of Collin County (2017-2018)
- Member, Dallas Challenge, Inc. (2015-2017)
- Member, Leadership Arts Institute (2013-2014)
- Yale Law School, JD, cum laude
- Carleton College, BA
- Texas
- New York
- US Court of Appeals for the Fifth Circuit
- US Court of Appeals for the Tenth Circuit
- US District Court for the Western District of Texas
- US District Court for the Northern District of Texas
- US District Court for the Eastern and Southern Districts of New York
