Mulher com cabelos castanhos compridos, vestindo um blazer escuro e uma blusa clara, sorrindo com confiança — uma profissional inspiradora entre os advogados de Chicago — em frente a prateleiras desfocadas e iluminação interna aconchegante.

Diane Hazel

Parceiro

Diane Hazel é uma advogada antitruste reconhecida nacionalmente e ex-funcionária do governo que representa clientes em litígios complexos e investigações de alto risco. Ex-advogada da Comissão Federal de Comércio (FTC) e da Procuradoria Geral do Colorado, Diane traz um profundo conhecimento das agências e perspicácia estratégica para o seu trabalho de defesa de clientes em investigações da FTC, do Departamento de Justiça e das Procuradorias Gerais estaduais.

Diane is a trusted advocate and litigator in some of the largest antitrust class actions in the country, with extensive experience in multidistrict litigation and federal court defense. Diane regularly represents clients facing allegations of price fixing, market allocation, monopolization, and other forms of alleged anticompetitive conduct. Her litigation practice spans a range of industries, with particular depth in technology, health care, manufacturing, and energy.

Clients value Diane’s professionalism, diligence, and clear communication. She takes a practical, business-minded approach to litigation and investigations—working closely with clients to understand their goals, minimize risk, and craft creative, effective legal strategies. Diane’s background as a former enforcer allows her to anticipate agency priorities and navigate complex regulatory landscapes with confidence.

In addition to her litigation and investigations work, Diane counsels clients on consumer protection matters, including compliance with FTC rules and issues related to fees and disclosures. She also advises on antitrust aspects of joint ventures, competitor collaborations, information sharing, distribution contracts, product pricing, and mergers, including Hart-Scott-Rodino (HSR) Act filings and merger reviews.

Prior to joining Foley, Diane served as a First Assistant Attorney General at the Colorado Attorney General’s Office, where she led the Antitrust Unit and supervised dozens of investigations and merger reviews. At the FTC’s Bureau of Competition Health Care Division, she investigated and prosecuted antitrust matters in the health care and pharmaceutical sectors. Diane was also awarded a Fulbright Grant by the U.S. State Department and spent a year in Namibia working with the Namibian government on antitrust and consumer protection initiatives.

Prémios e reconhecimentos

  • Recognized, Global Competition Review and Lexology Index, Future Leader – Competition (2025)
  • Recognized, Law Week Colorado, Barrister’s Best, Best Antitrust Lawyer, People’s Choice (2024)
  • Recognized, Law Week Colorado’s Barrister’s Best, Antitrust Lawyer (2023)
  • Recognized, 5820 Top Lawyers, Antitrust (2023-2024)
  • Recognized, Colorado Rising Stars by Super Lawyers®, Antitrust Litigation (2018, 2019)
  • Recipient, Colorado Attorney General’s Rookie of the Year Award (2021)
  • Recipient, National Association of Attorneys General, Antitrust Chair’s Writing Award (2020)

Filiações

  • Colorado Bar Association
  • District of Columbia Bar
  • American Bar Association, Section of Antitrust Law
    • Co-Chair, Competition Torts Committee (2023-present)
    • Vice-Chair, State Enforcement Committee (2020-2023)
    • Young Lawyer Representative, Trade, Sports & Professional Associations Committee (2018-2019)

Participação na comunidade

  • Legal Aid Foundation Board of Trustees
    • Secretary (2025-present)
    • Board Member (2024-present)
  • Colorado Ballet Auxiliary Board of Directors (2025-present)
  • Denver Zoo Leadership Council (2022-2025)
  • Washington Park Early Learning Center Board of Directors
    • President (2021-2024)
    • Secretary (2020-2021)
  • Denver Metro Chamber of Commerce, Leadership Denver (Class of 2023)
  • AfricAid Board of Directors (2018-2021)
  • Metro Chamber Health Care Committee (2016-2019; 2022-present)
  • Colorado Women’s Bar Association LIFT Mentoring Program

Apresentações e publicações

  • Panelist, “Defense Views on State Enforcement,“ American Bar Association Antitrust Magazine (August 27, 2025)
  • Co-author, “Federal Court Applies Antitrust Standard of Per Se Illegality to ‘Algorithmic Pricing’ Case,” Innovative Technology Insights (February 3, 2025)
  • Author, “FTC Announces Final Junk Fees Rule Applying to Live-Event Tickets and Short-Term Lodging,” Consumer Class Defense Counsel (January 17, 2025)
  • Co-author, “FTC and DOJ Withdraw Guidelines for Collaborations Among Competitors,” Legal News Alert (January 3, 2025)
  • Moderator, “Anticompetitive Conduct Is Best Determined by the FTC,” American Bar Association Antitrust Fall Forum (November 14, 2024)
  • Speaker, “Non-Compete Agreements,” Colorado Bar Association Business Law Institute (September 6, 2024)
  • Speaker, “The FTC Abolished Non-Competes: What That Means for Your Clients,” Colorado Bar Association (May 16, 2024)
  • Co-author, “FTC Issues Warning Letters on the Use of Algorithms to Recommend or Set Prices,” Innovative Technology Insights (March 6, 2024)
  • Author, “Private equity investments in physician practices draw regulatory scrutiny,” Medical Economics (August 2023)
  • Co-author, “An Analysis of the “Deputization” Theory of Section 8 of the Clayton Act,” The Antitrust Source (August 2023)
  • Author, “Colorado Antitrust Reform Carries Broad State Impact,” Law360 (August 3, 2023)
  • Quoted, “New Colo. Laws Alter Health Care, Antitrust Enforcement,” Law360 (June 9, 2023)
  • Author, “DOJ Antitrust Division and HHS OIG Enter into Partnership to Increase Coordination and Enforcement in Health Care,” Health Care Law Today (Dec. 13, 2022)
  • Co-author, “How to Assess Interlocking Directorates in Antitrust Ramp-Up” (Oct. 25, 2022)
  • Author, “FTC Imposes Civil Penalty for Faulty ‘Messenger Model’ Contracting,” Health Care Law Today (Oct. 13, 2022)
  • Panelist, “The Outlook for U.S. Antitrust,” Antitrust Texas Conference (Sept. 20, 2022)
  • Author, “FTC Releases Paper Opposing Certificates of Public Advantage for Health Care Transactions ,” Health Care Law Today (Aug. 25, 2022)
  • Moderator, “Drinking from the Legislative Firehose,” American Bar Association Antitrust Spring Meeting (April 2022)
  • Panelist, “A View from the AG’s Office: Topics in Antitrust and Consumer Protection Enforcement,” Colorado Bar Association (December 16, 2021)
  • Panelist, “The Outlook for U.S. Antitrust,” Antitrust Texas Conference (September 28, 2021)
  • Moderator, “Regulation of Social Media,” Annual Rocky Mountain Intellectual Property & Technology Law Institute (June 4, 2021)
  • Moderator, Colorado Attorney General’s Office National Privacy Day Forum (January 2021)
  • Co-author, “Class Action Settlements: Res Judicata, Release, and the Identical Factual Predicate Doctrine,” Idaho Law Review, Vol. 55 (2021)
  • Co-author, “Regulated Industries – Sports,” 2018 Annual Review of Antitrust Law Developments (March 2019)
  • Panelist, “Patent Settlement Agreements: Impact on Antitrust Enforcement Demystified,” The Knowledge Group Webinar (April 13, 2016)
  • Author, “Tying Arrangements: Do Your Pricing Policies Pass Muster Under the Antitrust Laws?” S. Law Magazine (Fall/Winter 2016)
  • Author, “Competition in Context: The Limitations of Using Competition Law as a Vehicle for Social Policy in the Developing World,” Houston Journal of International Law (2015)
  • Author, “Litigating with class: Considering a potential framework for class actions in Namibia,” Namibia Law Journal (2014)
  • Author, “Competition Commission of South Africa Initiates Private Healthcare Market Inquiry,” International Antitrust Bulletin (ABA Section of Antitrust Law) (December 2013)
  • Author, “The Economics of Rising Poultry Prices and Dairy Shortages,” Namibia Consumer News (November 2013)
  • Panelist, “Competition in Healthcare,” 7th Annual Conference on Competition Law, Economics & Policy (September 5, 2013)
  • Co-author, “Antitrust Issues Involving Intellectual Properties,” 2012 Annual Review of Antitrust Law Developments (March 2013)
Vista aérea de um bairro suburbano com fileiras de casas unifamiliares semelhantes, relvados verdes e ruas, projetando longas sombras à luz do sol — a poucos quilómetros de distância de um importante escritório de advocacia corporativa.
February 3, 2025 Innovative Technology Insights

Tribunal Federal aplica norma antitruste de ilegalidade per se a caso de “preços algorítmicos”

O software de precificação algorítmica continua a ser um foco tanto para os demandantes quanto para os reguladores em 2025.
A imagem mostra o edifício do Capitólio dos Estados Unidos com a sua cúpula proeminente e colunas clássicas sob um céu azul límpido, reflectindo a seriedade frequentemente associada aos principais escritórios de advogados e ambientes de escritórios de advogados empresariais.
January 22, 2025 Foley Viewpoints

O limite para notificação Hart-Scott-Rodino aumenta em US$ 6,9 milhões

As últimas duas semanas foram bastante movimentadas no mundo da Lei Hart-Scott-Rodino Antitrust Improvements Act de 1976 (15 U.S.C. § 18a) (HSR).
A imagem mostra o edifício do Capitólio dos Estados Unidos com a sua cúpula proeminente e colunas clássicas sob um céu azul límpido, reflectindo a seriedade frequentemente associada aos principais escritórios de advogados e ambientes de escritórios de advogados empresariais.
January 17, 2025 Consumer Class Defense Counsel

FTC anuncia regra final sobre taxas abusivas aplicável a bilhetes para eventos ao vivo e alojamento de curta duração

Em 17 de dezembro de 2024, a Comissão Federal de Comércio dos EUA anunciou a sua «Regra sobre Taxas Indesejáveis» definitiva para impedir certas práticas relacionadas com a fixação de preços nos setores de venda de bilhetes para eventos ao vivo e alojamento de curta duração.
O edifício do Capitólio dos Estados Unidos com colunas e uma cúpula, encimado por uma bandeira americana contra um céu azul - um símbolo inspirador para escritórios de advogados e para quem procura apoio em litígios.
3 de janeiro de 2025 Pontos de vista da Foley

FTC e DOJ retiram diretrizes para colaborações entre concorrentes

Em 11 de dezembro de 2024, o Departamento de Justiça dos Estados Unidos (DOJ) e a Comissão Federal de Comércio (FTC) (em conjunto, “as Agências”) retiraram conjuntamente as Diretrizes Antitruste para Colaborações entre Concorrentes de 2000 (“Diretrizes”). A retirada conjunta das Diretrizes esclarece a decisão das Agências de remover quaisquer salvaguardas antitrust. A retirada também foi notável, pois a ação das Agências ocorreu pouco antes da posse do governo Trump e da transição para um novo presidente da FTC.
November 14, 2024 Events

ABA Antitrust Law Section Fall Forum Debate: Anticompetitive Conduct is Best Determined by the FTC

During the Fall Forum of the American Bar Association Antitrust Law Section, Partner Diane Hazel will moderate a debate that will argue the pros and cons of whether anticompetitive conduct is best determined by the FTC.
October 14, 2024 Honors and Awards

Advogados da Foley nomeados para a lista dos melhores advogados da Law Week Colorado

As sócias da Foley & Lardner LLP, Emily Weber e Diane Hazel, e o consultor jurídico sénior Timothy Mohan foram reconhecidos na lista Barrister's Best 2024 da Law Week Colorado.