Markus is particularly experienced in liability issues and defense in class actions (Legal500). A competitor stated that he is an outstanding litigator (JUVE), clients highlight that he delivers high quality (JUVE), he has been described as cooperative, perfectly clear, always ready to talk (JUVE), and thinks in economic terms (JUVE).
Biography
Markus represents clients throughout the world in high-stakes disputes across a variety of industries and brings a strong international perspective to formal court proceedings, arbitration, and various other forms of dispute resolution, including mediations.
Markus has a national and international practice focused on technology, internet, and social media law, with a particular emphasis on collective redress, consumer protection, unfair competition, and data protection litigation. Markus has extensive trial experience defending the world's leading technology and platform companies in high-stakes disputes involving intermediary liability, data protection and personality rights, platform transparency obligations, and regulatory enforcement actions.
Markus is a recognized leader in Germany's evolving collective and mass redress landscape. He advises and represents major digital platforms in proceedings under Germany's new collective redress regime (VDuG), the Act on Injunctive Relief (UKlaG), and follow-on damages actions, including third-party funded profit disgorgement claims. His practice sits at the intersection of consumer protection law, unfair competition law (UWG), data protection law, product safety and platform regulation under the Digital Services Act (DSA), enabling him to develop integrated defense strategies that address clients' legal, financial, and reputational exposure holistically.
Markus coordinates pan-European defense strategies for major US and global platform operators, serving as a single point of contact to ensure consistency in legal and factual positioning across multiple jurisdictions.
Experience
Represents Amazon in multiple landmark proceedings in Germany, including one of the first collective redress actions ever brought under the VDuG and a third-party funded profit disgorgement action under Section 10 UWG.
Represents X (formerly Twitter) in some of the most significant social media litigation in Germany, including the first-ever collective redress action brought against X under the VDuG concerning alleged data protection violations, and a large-scale mass litigation involving more than 5,000 individual GDPR claims arising from alleged data scraping.
Represents TikTok in collective redress and injunctive relief proceedings concerning alleged consumer rights and data protection infringements, coordinating defense strategies across multiple European jurisdictions.
Represents Pinterest in collective action proceedings alleging violations of transparency obligations for recommender systems under the Digital Services Act (DSA).
Leads the representation of Vallourec in arbitration proceedings against its co-owners Salzgitter and Thyssenkrupp arising from a shareholder dispute over the HKM joint venture in Duisburg.
Representation of Commerzbank in a €280 million victory relating to a major M&A contractual dispute involving considerable reputational and financial risk, achieving a successful outcome before the Higher Regional Court (OLG) of Frankfurt am Main.
Representation of Deutsche Pfandbriefbank, Helaba, Nord/LB, HSH Nordbank, Berlin Hyp, Landesbank Berlin, and Sparkasse Cologne/Bonn in proceedings related to claims against HETA Asset Resolution AG.
Best Lawyer Germany in Litigation, Handelsblatt 2020-2026
Notable Practitioner, Litigation, Chambers Global Guide Germany 2025
Highly Recommended Lawyer: Dispute Resolution: Litigation, JUVE 2024/2025
Recommended Lawyer: Dispute Resolution & Dispute Resolution in the Financial Sector – Germany, Legal 500 Germany, 2024
"Legal Risk for Global Tech Products: Navigating Global Regulations", 6/23/2022: TechGC, San Francisco Fireside Dinner, San Francisco, California
"Praxisseminar Cyber-Security » Cyber Attack & Data Breach – Preparedness & Response", 5/26/2020: Seminar in cooperation with Deutsche Fachverlag, White & Case Office Frankfurt, Germany
"Collective Litigation in Germany, the EU and the U.S.: Model Declaratory Proceedings under Scrutiny: Class action light?", 24/10: Client Seminar – White & Case Office – Frankfurt, Germany
"Organhaftung aktuell – Vorbeugen, Vermeiden, Verfolgen", 13/03/2018: WM Seminar, Sofitel Frankfurt Opera, Frankfurt
"Negative interest rates – Update 2016 (Negative Zinsen – Update 2016)", 13/07/2016: White & Case Seminar, Frankfurt
"Negative interest rates in the lending, deposit and capital markets business (Negative Zinsen im Einlagen-, Kredit-, Kapitalmarktgeschäft)", 07/07/2015: White & Case Seminar, Frankfurt (together with Prof. Peter Mülbert, Karsten Wöckener and Sebastian Glock)
"HETA ASSET RESOLUTION AG - practical Update: current situation - recent developments - future outlook (HETA ASSET RESOLUTION AG - Praktiker-Update: Bestandsaufnahme - Aktuelle Entwicklungen - Ausblick)", 27/05/2015: White & Case Spring Seminar Series (together with Roger Kiem, Dennis Heuer, Karsten Wöckener, Henning Berger)
International Comparative Legal Guide - Enforcement of Foreign Judgments 2022, Laws and Regulations Germany, Chapter 13, March 2022 (co-author with Dominik Stier and Kristof Waldenberger)Lexology GTDT Technology Disputes 2022 - GermanyTrends in German commercial litigation, The Legal 500, In-House Lawyer, Autumn 2021 (co-author with Detlev Gabel, Sonja Hoffmann, Alexandra Diehl, Alissa Arms, Swantje Behm)
Cyber-Security Legal Handbook (Rechtshandbuch Cyber-Security), Gabel/Heinrich/Kiefner (Eds.), Frankfurt am Main, 2019, Chapter 10, Litigation and Liability (Co-author with Dominik Stier)
Securities Litigation in Germany, Lexology
Federal Court: D&O Insurance Liability Cases – Broad Interpretation of the Term "Third Party" in § 108 of the Insurance Contract Act (VVG), Compliance-Berater, Issue 8, pp. 304-308, 2016, (BGH: Innenhaftungsfälle der D&O-Versicherung – weite Auslegung des Begriffs „Dritter“ in § 108 VVG) (co-author with Stefan Deller)
Negative interest rates affect capital markets law, p.9, Börsen-Zeitung, August 8th 2015, (Negative Zinsen beeinflussen Kapitalmarktrecht) (co-author with Karsten Wöckener)
US antitrust standards or the end of the assignment model? - Collective enforcement of compensation claims de lege lata, BB, Issue 149, Pages 1795-1801, 2014, (Amerikanische Verhältnisse im Kartellrecht oder Ende des Abtretungsmodells? - zur gebündelten Durchsetzung von Schadensersatzansprüchen de lege lata) (co-author with Lars Teigelack)
Higher Regional Court of Schleswig-Holstein: Prerequisites for Tort Liability of the Management Board of an Investment Advisory Company. Commentary on the decision of the Higher Regional Court of Schleswig-Holstein of May 23, 2013 – 5 U 140/12 , Compliance Berater, Issue 8, pp. 349–352, 2013, (OLG Schleswig-Holstein: Voraussetzungen einer Deliktshaftung des Vorstandes einer Anlagevermittlungsgesellschaft. Anmerkung zum Urteil des OLG Schleswig-Holstein vom 23.5.2013 – 5 U 140/12) (co-author with Stefan Deller)
Commentaries on §§ 23a, 25a of the German Banking Act (Kommentierung der §§ 23a, 25a KWG), Kreditwesengesetz. Ed. Andreas Schwennicke und Dirk Auerbach. 2nd ed., Munich, 2012
Investment advice and prospectus liability limitation periods dependent on knowledge, NZG, Issue 3, pp. 94–97, 2011, (Die kenntnisabhängige Verjährung bei Anlageberatung und Prospekthaftung)
Obligation to secure the insolvency estate and breach of duties by the supervisory board, NJW, p. 192 et seqq., 2011, (Massesicherungspflicht und Versagen des Überwachungsorgans) (co-author with Alexander Kiefner)
Court decisions in 2009/2010 on prospectus liability , RdF, Issue 2, p. 98 et seqq., 2011, (Rechtsprechungsreport zur Prospekthaftung in den Jahren 2009/2010) (co-author with Mareile Müller-Felsch)
Banking Supervision: Second Amendment of the MaRisk Minimum requirements for risk management , BKR, No. 8, pp. 309–316, 2009, (Die Zweite MaRisk-Novelle in der Bankenaufsicht)
