rothorn legal | international disputes | Nathalie Voser

Prof. Dr. Nathalie Voser

LL.M. (Columbia)
Partnerin // Rechtsanwältin

othorn legal | international disputes
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Nathalie Voser is a founding partner of rothorn legal. She has acted as counsel and arbitrator in a vast number of arbitrations under many major institutional rules. She has also advised clients involved in complex multi-jurisdictional disputes before state courts.

Nathalie Voser is well known for her expertise in engineering and construction, (renewable) energy related projects, oil and gas, pharmaceutical and automotive industries. She has considerable experience in research and development, distribution and license agreements, joint ventures as well as mergers and acquisitions. She is appointed as arbitrator in both commercial and investment treaty arbitrations.

She is recognized by the major directories. According to Who’s Who Legal Arbitration 2020, Nathalie is “a high flyer” in the European arbitration field, for whom peers “only have praise“. They note, “She never fails to impress – neither on the law, nor on interpersonal skills as an arbitrator”. Who’s Who Legal Arbitration 2019 says Nathalie has an excellent reputation in the construction and energy sectors, with peers lauding her as “one of Switzerland’s brightest stars“.

Among other functions, Nathalie Voser is currently Vice President of the London Court of International Arbitration (LCIA) and the president of the European User’s Council of the LCIA. She is a board member of the Swiss Arbitration Association and the Vienna International Arbitration Chamber (VIAC) and a member of the ICC Arbitration Commission.

Nathalie has assisted in a significant way in various arbitrations related project, such as the 2004 IBA Conflict of Interest Guidelines, the revision of the 2012 ICC Arbitration Rules, the 2017 SCC Rules and the 2020 IBA Rules on the Taking of evidence.

Finally, Nathalie is the author of many arbitration-related articles and of a leading textbook in arbitration, now in its fourth edition.


Nathalie Voser is currently acting as or has acted as:

  • Counsel for an internationally renowned constructor in multiple complex construction disputes (including both litigation and arbitration proceedings) against both the owner and the subcontractor concerning structural defects in a cooling tower of a currently active power station.
  • Counsel for an internationally renowned seller of turbines for offshore electricity production in a dispute regarding alleged delays, defects and further shortcomings in the context of the construction of a large offshore oil platform.
  • Counsel for an Israeli company (and its international parent company) acting as EPC contractor of a large scale solar thermal power station in three ICC arbitrations regarding disputes arising out of mechanical, electrical and piping erection work.
  • Counsel for a German company in ICC arbitration against a Kazakh company in a dispute under a series of supply and engineering contracts related to the design, delivery of equipment and related ancillary services concerning a ferrochrome smelting facility.
  • Co-arbitrator in ICC arbitration regarding the dispute between two public mobile network operators regarding the applicable tariff for international roaming services; Swiss seat and Swiss law applicable.
  • President in SCAI arbitration proceedings concerning unpaid steel delivered under bills of exchange and insured by a credit insurance policy which the insurer, based on assignments, is claiming directly from the buyer; Swiss seat, English law applicable.
  • President in DIS Rules arbitration, involving two German companies in a dispute regarding price adaptation under a long-term gas storage agreement; German seat and German law applicable.
  • Co-arbitrator, ICSID arbitration involving insolvent German construction company and its claims against Turkmenistan under the Germany-Turkmenistan BIT.
  • Co-arbitrator, ad hoc arbitration under UNCITRAL Arbitration Rules 1976, multi-party arbitration involving a Eurasian state entity and a Eurasian state agency against a foreign investor in a contractual oil & gas dispute under a production sharing contract.

 Nathalie Voser has written inter alia the following publications:

  • The Consequences of Achmea on Arbitrations Seated in Switzerland, in: The future of Investment Treaty Arbitration in the EU: Intra-EU BITs, the Energy Charter Treaty, and the Multilateral Investment Court, C. Baltag/A. Stanic (ed.), Wolter Kluwer 2020, p. 115 – 142. (co-authored with Sebastiano Nessi).
  • Besonderheiten einiger wichtiger Jurisdiktionen – Schweiz, in: Salger/Trittmann, Internationalen Schiedsverfahren, Praxishandbuch, 2019
  • Know How Construction Arbitration Switzerland 2018, published by the Global Arbitration Review (GAR), 2018 (co-authored with Elliott Geisinger, Christopher Boog and Katherine Bell)
  • E-Publication on conflict of interest in Arbitration, in Kluwer Arbitration Blog “Has Acting as Arbitrator Become a Risky Business?”, 2018
  • “Schiedsverfahren und anwendbares Recht”, in Hellwig Torggler et al (Hrsg) “Handbuch Schiedsgerichtbarkeit, 2nd ed, Verlag Österreich, 2017, pp. 249-278 (co-authored)
  • The Swiss Perspective on Parties in Arbitration: “Traditional Approach with a Twist regarding Abuse of Rights” or “Consent Theory Plus”, in: The Evolution and Future of International Arbitration, International Arbitration Law Library Vol. 37, Alphen aan den Rijn: Kluwer Law International, 2016, pp. 161–181.
  • International Arbitration – Comparative and Swiss Perspectives, 4th, Zurich: Schulthess, Baden-Baden: Nomos, 2021 (co-authored with Daniel Girsberger)

Nathalie Voser graduated summa cum laude from the University of Basel and was admitted to the bar in Switzerland in 1990. In 1992, she became a juris doctor with summa cum laude and in 1994 earned an LL.M. from Columbia University (New York) with honors. In 2005, she received the venia docendi for private law, conflicts of laws and comparative law and, in 2014, she was awarded the title of Professor in private law, arbitration law, private international law and comparative law by the University of Basel, where she regularly teaches courses in commercial arbitration and other areas of Swiss private law.