Düsseldorf
He has acted as counsel and arbitrator in more than 300 arbitrations, including ad hoc proceedings and cases administered under the rules of many leading arbitration institutions such as the ICC, LCIA, DIS, ICSID and UNCITRAL.
As counsel, he represents both private investors and international corporations, as well as sovereign states, and state-owned enterprises in a range of significant, complex and, frequently, cross-border disputes.
Siegfried has extensive experience with both commercial and investment arbitration. His work as counsel and arbitrator spans a wide variety of disputes including post M&A and other corporate transactions (e.g. joint ventures); engineering; energy and construction cases; intellectual property disputes such as licensing and distributorship agreements, investment protection cases involving a multitude of bilateral investment treaties; and disputes concerning financing arrangements.
In addition to his work as counsel and arbitrator, Siegfried also appears as an expert witness before German courts, courts in the United States and the United Kingdom and foreign regulatory institutions.
He is admitted to practice as an attorney-at-law in both Germany and New York. Accordingly, his legal practice also focuses on German-American legal transactions.
Siegfried has been recommended consistently by many legal publications as arbitrator and counsel for arbitration. As in previous years, the Lexology Index (formerly Who's Who Legal) has featured Siegfried as a "Global Elite Thought Leader" in Arbitration, Chambers Global 2026 describes him as a "star individual" and a "towering figure in the German and European arbitration market" who is "often sitting in complex disputes under ICC, ICSID AND UNCITRAL rules, while also being well versed in a number of other arbitration rules" and "sought after as an arbitrator for commercial and investment cases."
Siegfried has served on the boards and panels of many leading arbitration institutions. He has previously served on the Advisory Board of the American Arbitration Association (2009 to 2020) and the Panel of Conciliators of the International Centre for Settlement of Investment Disputes (ICSID) (2011 to 2017). He was a member of the Board of the German Arbitration Institute (DIS) (2012 to 2022) and served on the DIS Council (since 2022 to 2025). He also served as Chairman of the Mediation Committee of the International Bar Association (IBA) (2007-2008).
Siegfried regularly publishes in the field of international arbitration and comparative law and is the co-editor of the German Arbitration Journal (Zeitschrift für Schiedsverfahren (SchiedsVZ)). He also frequently appears on panels and holds lectures on international arbitration and comparative law, with a particular focus on U.S. law. Siegfried is an honorary professor at the Faculty of Law at Heinrich Heine University Düsseldorf, where he has taught international commercial arbitration and international civil procedure law for 25 years.
Since 2013, he has represented the Grand Duchy of Luxembourg as Honorary Consul in North Rhine-Westphalia.
Siegfried Elsing co-founded the German law firm Hölters & Elsing in 1989 and oversaw its the merger with Orrick in 2008.