Deirdre Carroll is a partner in the Brussels and London offices of Wilson Sonsini Goodrich & Rosati, where her practice focuses on global mergers, agency investigations, and compliance counselling. She also works closely with Wilson Sonsini’s data protection and privacy team to provide clients with integrated, strategic advice on data-related antitrust counselling and digital platform regulation, including the EU’s Digital Markets Act.
Deirdre expertly navigates the complexities of antitrust regulations across diverse industries and jurisdictions with a robust track record representing clients before the European Commission (EC) and the UK Competition and Markets Authority (CMA). Her extensive experience includes securing clearance for some of the most high-profile and complex transactions on a global scale.
She has experience across a wide range of sectors, including tech, advertising (adtech), financial services, life sciences, aviation, basic industries, and mining.
Deirdre maintains an active pro bono practice. She is a recipient of the firm's John Wilson Award, which is presented annually to attorneys who have demonstrated a significant commitment to the firm's pro bono clients.
Prior to joining the firm in 2015, she was an intern at the European Commission's DG Competition in the Antitrust—Media unit.
Deirdre is a native English speaker, and she is fluent in Irish and French.
Deirdre Carroll is a partner in the Brussels and London offices of Wilson Sonsini Goodrich & Rosati, where her practice focuses on global mergers, agency investigations, and compliance counselling. She also works closely with Wilson Sonsini’s data protection and privacy team to provide clients with integrated, strategic advice on data-related antitrust counselling and digital platform regulation, including the EU’s Digital Markets Act.
Deirdre expertly navigates the complexities of antitrust regulations across diverse industries and jurisdictions with a robust track record representing clients before the European Commission (EC) and the UK Competition and Markets Authority (CMA). Her extensive experience includes securing clearance for some of the most high-profile and complex transactions on a global scale.
She has experience across a wide range of sectors, including tech, advertising (adtech), financial services, life sciences, aviation, basic industries, and mining.
Deirdre maintains an active pro bono practice. She is a recipient of the firm's John Wilson Award, which is presented annually to attorneys who have demonstrated a significant commitment to the firm's pro bono clients.
Prior to joining the firm in 2015, she was an intern at the European Commission's DG Competition in the Antitrust—Media unit.
Deirdre is a native English speaker, and she is fluent in Irish and French.
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Co-author, “Consumer Protection in the UK: Update on Reforms Taking Effect in 2025 and 2026,” Wilson Sonsini Alert, July 11, 2025
Co-author, “A View Across the Pond: A Change of Direction for Antitrust Enforcers in the EU and UK?” Wilson Sonsini Alert, February 6, 2025
Co-author with L. Boylan and B. Buffier, "CMA Levies Record Fine on Facebook for Deliberate Breach of Hold-Separate Order in Probe of GIPHY Takeover," Wilson Sonsini Alert, October 21, 2021
Co-author with S. Taheny, “European Commission Publishes Guidance Paper on Member State Referrals for Merger Review Even Where National or EU Thresholds Are Not Met,” Wilson Sonsini Alert, April 8, 2021
Co-author with L. Signoret, “Incoming: Increased UK Enforcement in Digital Markets,” Wilson Sonsini Alert, April 8, 2021
Co-author with C. Burton and others, “European Commission Proposes New Rules for Digital Platforms,” Wilson Sonsini Alert, January 12, 2021
Co-author, “Consumer Protection in the UK: Update on Reforms Taking Effect in 2025 and 2026,” Wilson Sonsini Alert, July 11, 2025
Co-author, “A View Across the Pond: A Change of Direction for Antitrust Enforcers in the EU and UK?” Wilson Sonsini Alert, February 6, 2025
Co-author with L. Boylan and B. Buffier, "CMA Levies Record Fine on Facebook for Deliberate Breach of Hold-Separate Order in Probe of GIPHY Takeover," Wilson Sonsini Alert, October 21, 2021
Co-author with S. Taheny, “European Commission Publishes Guidance Paper on Member State Referrals for Merger Review Even Where National or EU Thresholds Are Not Met,” Wilson Sonsini Alert, April 8, 2021
Co-author with L. Signoret, “Incoming: Increased UK Enforcement in Digital Markets,” Wilson Sonsini Alert, April 8, 2021
Co-author with C. Burton and others, “European Commission Proposes New Rules for Digital Platforms,” Wilson Sonsini Alert, January 12, 2021