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Mattis Leson, LL.M. (University of Edinburgh)
Mattis Leson, LL.M. (University of Edinburgh)
Rechtsanwalt
Associate, Antitrust and Competition
T +49 30 214 802 700
E mattis.leson@blomstein.com
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Mattis Leson specialises in German and European antitrust and competition law. He advises German and international clients before the German and European courts, the European Commission and the Federal Cartel Office.

Mattis is admitted to the Bar in Germany (Rechtsanwalt). He is a co‑founder of the association GrundGesetzVerstehen e.V.

Languages: German, English

CV

Mattis studied economics and law (B.Sc.) as well as law at the University of Münster and the University of Edinburgh. He completed his legal clerkship at the Higher Regional Court of Hamm, with stages including the European Commission (DG COMP) in Brussels.

After passing his second state examination, he initially worked as a research assistant at the Chair of Public and European Law (Prof. Dr. Christian Calliess) at the Free University of Berlin, before subsequently joining BLOMSTEIN as a research assistant.

His doctoral research focuses on the principle of solidarity within the Economic and Monetary Union (ongoing Ph.D. project).

Publications

  • Vertikalvertrieb nach Chloé, Gucci und Loewe, NZKart, 15 June 2026, p. 283 (with Elisa Hauch)

  • Moving towards a SAFE Defense Policy in Europe, Verfassungsblog 09/2025

  • Umkämpfte Meilensteine – Rechtsstaatlichkeitskonditionalität bei NextGenerationEU, Verfassungsblog 10/2024