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Thomas Lennarz

Dr. Thomas Lennarz

Rechtsanwalt | Head of Dispute Resolution, CMS Germany

CMS Hasche Sigle
Schoettlestraße 8
70597 Stuttgart
Languages German, English

Thomas Lennarz focuses on dispute resolution, representing companies and entrepreneurs before state courts as well as in arbitration proceedings and advising his clients in complex out of court negotiations. Thomas specialises in corporate disputes (including post-M&A disputes), general civil and commercial law matters as well as climate change litigation. He also regularly acts as an arbitrator.

Thomas joined CMS in 2004. In 2007, he qualified as a commercial mediator and in 2008 he obtained the International Commercial Arbitration Diploma from the Chartered Institute of Arbitrators (London/Oxford). In 2009, he worked in the legal department of Linde AG in Sydney before being made a CMS partner in 2012. Alongside his legal practice, Thomas also teaches at the University of Heidelberg. Since 2012, he has been head of the firm's Corporate Litigation Group.

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Listed for Conflict Resolution

Deutschlands beste Anwälte 2020 – Handelsblatt in Kooperation mit Best Lawyers

Listed as "Future Leader"

Who's Who Legal 2019 - Arbitration

"Recommended for Corporate Litigation"

JUVE German Commercial Law Firms 2019 (GCLF)

"Thomas Lennarz is also highly recommended for his expertise in the area."

Who's Who Legal 2017

Listed in "Rising Stars in Commercial Arbitration"

Expert Guides Rising Stars, 2016

Relevant experience

  • Representation of several large family enterprises in corporate law disputes (dismissing directors, redemption of shares), etc.
  • Representing one of the world’s leading automotive suppliers in a complex post-M&A dispute: claim for damages after the acquisition of a non-German group due to several breaches of warranty as stated in the sales and purchase agreement; defending the client against claims to pay the remaining purchase price; preliminary injunction proceedings in Germany, Poland and Cyprus
  • Representing a leading energy company in the context of challenging a sales and purchase agreement on the grounds of willful deceit: asserting warranty claims; dispute over earn-out claims
  • Advising in a dispute between two joint venture partners from the public services sector: Representing a globally operating implant manufacturer in product liability cases
  • Defending a large wind park operator in a dispute over the validity of capital increases
  • Chairman, co-arbitrator and sole arbitrator in arbitration proceedings
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  • 2004: Research assistant for civil, commercial and business law at the University of Passau
  • 2003: Second state examination in law in Düsseldorf and PhD under the supervision of Prof. Dr. M. Schweitzer at the University of Passau
  • 2000: First state examination in law in Bonn
  • Graduated from the University of Bayreuth’s business lawyer course
  • Law studies at the Universities of Bayreuth, Vienna and Bonn including stints abroad, amongst others, in the USA and New Zealand
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  • German Institution of Arbitration (DIS)
  • Chartered Institute of Arbitrators (CIArb), chairman of the German chapter
  • Alumni der Wirtschaftsjuristen der Universität Bayreuth
  • American Chamber of Commerce in Germany (AmCham)
  • German-American Lawyers‘ Association (DAJV)
  • DIS 40 - Deutsche Initiative junger Schiedsrechtler (Regionalkoordinator bis 2015)
  • Mitglied des Prüfungsausschusses für den Fachanwalt Internationales Wirtschaftsrecht
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  • Arbitration, Doing Business in Europe, 2019, Sweet & Maxwell (together with Dr. Dorothee Ruckteschler)
  • Konfliktlösung ohne Gericht — Wirtschaftsmediation, Coaching, Nachhaltigkeit (ed.: Schweizer/Hehn), 2019, Berliner Wissenschafts-Verlag
  • „Schiedsverfahren oder staatliche Gerichtsverfahren – was ist besser?“, JA 2012, page 801 ff.
  • Schiedsvereinbarung und das selbständige Beweisverfahren: Ein Widerspruch? ibr-online 2012, 1050
  • Die neuen Schiedsverfahrensregeln der ICC - Auswirkungen auf FIDIC-Verträge, ibr-online 2012, 1048
  • Die DIS-Tool-Box zur alternativen Streitbeilegung – neue Regeln der Deutschen Institution für Schiedsgerichtsbarkeit, CMS-Report XVII, Januar 2011
  • Das deutsche Mediationsgesetz nimmt Gestalt an, CMS-Report XVII, Januar 2011
  • Germany: GmbH-shareholder disputes now arbitrable, The International Journal of Arbitration, Mediation and Dispute Management (76) 2010, p. 305 ff
  • German courts forbid double enforcement of foreign arbitral awards, in: CMS Dispute Resolution Newsletter 2010
  • Kapitel “Arbitration”, in: “Doing Business in Germany”, CCH Verlag 2008
  • EUGH: Übersetzung der Anlagen einer Klage bei Zustellung im Ausland?, (Anmerkungen zu EuGH, 08.05.2008, C-14/07 – Weiss und Partner), in: Der Betrieb, Status:Recht 2008, p. 200 f
  • European Court of Justice: Annexes to a Statement of Claim should be translated if the Claim is to be served within the EU, CMS Dispute Resolution Newsletter 2008
  • 7 Regeln für eine schnelle, einfache und gute Schiedsklausel, in: BetriebsBerater 2007, p. 1007 ff
  • The Third Man - The role of third parties in international arbitration, in: Legal Business Arbitration Report 2007, p. 47 ff
  • Eingeschränkte Schiedsfähigkeit von GmbH-Beschlussmängelstreitigkeiten, CMS Report XIV, Oktober 2007, p. 82 ff
  • Mediation als Konfliktlösung bei Gesellschafterstreitigkeiten, CMS Report XIV, Oktober 2007, p. 85 ff
  • Parallele Verfahren mit identischem Schiedsgericht als Lösung für Mehrparteienkonflikte?, in: SchiedsVZ 2006, p. 287 ff
  • Ernennung von Schiedsrichtern in Schiedsverfahren mit mehr als zwei Parteien, CMS Report XII, Mai 2006, p. 101 ff
  • Die Rechtsprechung des EuGH und des Gerichts 1. Instanz zu prozessualen Fragen des Verfügungsgrundsatzes und der Fristen, Peter Lang Verlag 2004, (Dissertation)
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Lectures list

Lecturing activities:

  • Guest lecturer involved in training trainee lawyers at Stuttgart Higher Regional Court on how to conduct negotiations and mediation (since 2010)
  • Lecturer on civil law at the University of Heidelberg (since 2007)
  • Lecturer on arbitration and mediation under German law at the University of War-saw (until 2011)


  • Climate change – new legal challenges for companies, Stuttgart, February 2019
  • Experts in arbitration proceedings, Stuttgart, December 2018
  • Alternative dispute resolution 2018 – negotiations between the FBI, policy and blockchain, Elmau, June 2018
  • The new arbitration rules of the German Institution of Arbitration (DIS) and the consequences for medium-sized companies, Gerstetten, among others, April 2018
  • Do arbitration proceedings and civil proceedings take too long? Does accelerating proceedings lead to quality loss? Stuttgart, September 2017
  • Alternative dispute resolution 2017 – conflicts in times of fake news, the Panama Papers and Brexit, Elmau, May 2017
  • New arbitration rules abound – required action for your contracts, Stuttgart, April 2017
  • Arbitral tribunals facing criticism – rightly so? Wiesbaden, October 2017
  • Do disputes always have to end in court? ADR in practice, Stuttgart, September 2016
  • Alternative dispute resolution 2016 – successful crisis management, Elmau, June 2016
  • Alternative dispute resolution - are you ready for negotiations? (moderation); Elmau, June 2015
  • The hot topic of liability - liability risks after M&A transactions; Stuttgart, April 2015
  • Transparency, TTIP and Toll Collect - arbitration proceedings in times of crisis?; Stuttgart, March 2015
  • Alternative dispute resolution - conflict management in German companies (moderation), Elmau, November 2014
  • What is (still) permitted? Preparing witnesses in arbitration proceedings and state court proceedings (moderation), Stuttgart, July 2014
  • New trends in arbitration, Stuttgart, May 2014
  • Mediation 3.0 – alternative dispute resolution: Current developments, Elmau, November 2013
  • The legal framework for mediation in Germany and in the European Union, Berlin, November 2013
  • Challenges in preparing effective damages evidence, Istanbul, October 2013
  • Guerrilla tactics or fair play? – Success factors during dispute resolution (moderation), Stuttgart, July 2013
  • Enforcement of judgments under the new Brussels I Regulation, Stuttgart (webinar), May 2013
  • Mediation 2.0 – conducting negotiations for your company, Elmau, November 2012
  • The new arbitration rules of the ICC - practical implications, Stuttgart, February 2012
  • Mediation in the future - how to conduct successful negotiations in mediation proceedings, Munich, January 2012
  • Efficient dispute resolution in plant construction – Between Scylla and Charybdis?, Stuttgart, October 2011
  • Mediation - a luxury for your company?, Elmau, September 2011
  • How to draft good and efficient arbitration clauses, Stuttgart (webinar), June 2011
  • The Americanisation of the German legal system, Stuttgart, March 2011
  • Avoiding a Tower of Babel – challenges in international plant engineering projects and how to deal with them, Frankfurt am Main, February 2011
  • Shareholder disputes - scorched earth or constructive dispute resolution?, Stuttgart, November 2010
  • Pitfalls to avoid when drafting arbitration clauses, Stuttgart, July 2010
  • Does a dispute always have to end up in court? – Individual dispute resolution for in-court and out-of-court disputes, Frankfurt am Main, April 2010
  • Will disputes become increasingly expensive? – Cost drivers in state legal proceedings, arbitration and mediation, Stuttgart, April 2010
  • Can a dispute be settled out of court? Arbitration proceedings in corporate law, University of Heidelberg, April 2010
  • How to resolve stalemate in joint ventures, Frankfurt am Main, April 2008
  • How to draft a good mediation clause, Munich and Upper Bavaria Chamber of Industry and Commerce, October 2007
  • Seven rules on how to draft quick, simple and effective arbitration clauses, Stuttgart, October 2007
  • Arbitration proceedings in corporate law, Stuttgart, May 2007
  • The exclusion and dismissal of shareholders and directors in a GmbH, Frankfurt am Main, March 2007
  • The recognition and enforcement of judgments in civil and commercial matters (Brussels I), Brussels, May 2005
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