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Sebastian advises and represents principals and contractors on all issues of construction and architects’ law. A further key practice area is insolvency law. He is active both in and out of court in both areas. His activities include providing legal support for construction projects, securing claims and enforcing rights in the event of the (imminent) insolvency of one of the parties. He also provides crisis-related advice to managing directors and shareholders and advises on insolvency avoidance law in order to avoid imminent repayment claims. His clients include public and private clients and contractors as well as large and medium-sized companies and private building owners.

Curriculum vitae

  • Studied law at the University of Hamburg, 2011 to 2016
  • Research assistant at the Chair for Civil Law, Civil Procedural and General Procedural Law with Prof. Dr. Reinhard Bork in Hamburg with a research visit to the University of Oxford (Harris Manchester College), 2016 to 2019
  • PhD in insolvency contract law, 2016 to 2019
  • Legal clerkship in Hamburg and London, 2019 to 2021
  • Lawyer at Kapellmann since 2021

Further qualifications and memberships

  • Lecturer at the University of Hamburg, 2019 to 2022
  • Member of the North German Insolvency Law Forum Hamburg e. V.
  • Member of ARGE Baurecht at the German Bar Association
  • Permanent contributor to the juris practice report on private construction law


Books and book contributions

Zeyns, Die anhängige Widerklage im Forderungsfeststellungsverfahren gem. §§ 174 ff. InsO, ZRI 2022, 358-363

Zeyns, Der Bau- und Bauträgervertrag in der Doppelinsolvenz, ZRI 2022, 569-575

Zeyns, (Insolvenzrecht und Bauvertragsrecht): Das Kündigungsrecht des Bestellers in der Unternehmerinsolvenz, ZIP 2018, S. 8-15

Annotations on court decisions

Lederer/Zeyns, Zur Darlegungslast einer Kündigungsvergütung und zur Kündigung aus wichtigem Grund wegen Insolvenz, Anmerkung zu OLG Dresden 22. Zivilsenat, Urteil vom 23.06.2023 - 22 U 2617/22, jurisPR-PrivBauR 5/2024 Anm. 2

Zeyns, Darlegung der Sicherungshöhe einer § 650f BGB-Bürgschaft im Falle eines beidseitig gekündigten Bauvertrages, Anmerkung zu OLG Stuttgart 10. Zivilsenat, Urteil vom 17.01.2023 - 10 U 91/22 jurisPR-PrivBauR 7/2023 Anm. 3

Zeyns, Zuständigkeit: Drittwiderklage gegen die Vertragserfüllungsbürgin, Anmerkung zu OLG Frankfurt 11. Zivilsenat, Beschluss vom 17.11.2022 - 11 SV 39/22, jurisPR-PrivBauR 3/2023 Anm. 1

Zeyns, Fristsetzung gemäß § 640 Abs. 2 BGB: Erneute Rüge bereits gerügter Mängel erforderlich?, Anmerkung zu OLG Schleswig 1. Zivilsenat, Urteil vom 10.12.2021 - 1 U 64/20, jurisPR-PrivBauR 10/2022 Anm. 3

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