passion for economy

dedicated, communicative, competent

Niels Frank Partner Vita Niels studied economics with a focus on industrial organisation at the University of Hamburg and the Christian-Albrechts-Universität Kiel. Niels has 20 years of experience working on numerous antitrust matters involving the assessment of cartel damages (inter alia, cement, car glass, TV advertising, sugar, trucks, ethylene), the effects of horizontal and non-horizontal mergers (third party in Telefónica/E-Plus) as well as abuse of dominance cases concerning conditional rebates, bundling and access to essential facilities. His industry experience includes fast moving consumer goods, TV-advertising, retailing, construction materials, business insurance, paper wholesale, airport infrastructure, telecommunication and services related to the postal sector. Niels frequently acts as a party expert in court proceedings providing written and oral expert statements. In the UK “second wave truck proceedings” Niels currently (2024) acts as the claimants’ expert on the issues of umbrella damages, resale pass-on, truck-dependent services pass-on and supply pass-on by local authorities before the Competition Appeal Tribunal (CAT). Niels has published papers in the Journal of Competition Law and Economics, the Journal of European Competition Law and Practice, Zeitschrift für Wettbewerbsrecht (Journal of Competition Law) and Wirtschaft und Wettbewerb (Competition Law and Economics). Between 2007 and 2021 Niels has lectured on competition economics and competition policy at the University of Bayreuth (Germany). He is a board member of the Competition Litigation Forum e.V. Niels is consistently recognized as a thought leader in the field of competition economics by Lexology/Who’s Who Legal. In 2023, leading German legal news outlet Juve ranked him 3rd among the 20 most renowned competition economists in Germany.
Dr. Gunnar Oldehaver Partner Vita
Dr. Steffen Sirries Partner Vita Steffen is a highly experienced academic and economic consultant. He regularly supports the antitrust community by providing expert insights on cartel detection methods, market dominance, and abuse cases, often working on the intersection of regulation and economic policy. His consulting expertise spans across international cartel litigation, antitrust cases, and regulatory compliance proceedings, with notable involvement in high-profile cases across multiple jurisdictions. He has worked extensively on cases such as the European Trucks Cartel, the Ethylene Purchasing Cartel, the Metal Forging Cartel, and the German Sugar Cartel. His international consulting engagements include cases in Germany, the UK, Poland, the Netherlands, Austria, and Hungary providing economic expertise in diverse regulatory environments. Steffen regularly advises on abuse of dominance cases, including the well-known Google Shopping abuse of dominance case in the digital-platform industry, as well as complex antitrust discount agreements in sectors such as TV-commercial advertising or the FMCG sector. His consulting work also extends to regulatory matters, working closely with national and European competition authorities. In addition to his casework, Steffen and his Partners at Lademann & Associates GmbH lead a team of 10 specialized economists, where they deliver advanced economic analysis for competition litigation, regulatory proceedings, and market investigations. His team is regularly involved in providing expert economic testimony, quantifying damages in cartel cases, and offering strategic advice to clients in a variety of industries. He holds a Professorship in Economics at Kutaisi International University (since 2020), where he lectures on competition economics, auction theory, empirical methods, as well as economic principles, bridging the gap between theoretical research and applied work. Steffen has developed significant academic expertise, particularly in the field of international trade, industrial organization, migration and labor markets, auctions and incentive mechanisms. His academic work complements his professional advisory work on national and EU-wide competition issues. Steffen earned his PhD in Economics from the University of Bayreuth in 2016, with a dissertation focused on international trade and migration, using structural and quantitative methodologies. His educational background includes a degree in business administration from RWTH Aachen University, with specializations in business taxation, corporate strategies in competition, and energy and process engineering. He is actively involved in several prestigious associations, including the German Association of Economists (Verein für Socialpolitik), the European Economic Association (EEA), the Competition Litigation Forum (c-l-f), the Studienvereinigung Kartellrecht, the Association of Competition Economists (ACE), the European Association for Research in Industrial Economics (EARIE) as well as the Georgian Economic Association (GEA). He is a frequent speaker at both scientific and business conferences, discussing the latest trends in competition economics and litigation. By combining in-depth academic expertise with practical experience in international consulting and regulatory work, Steffen has become a trusted advisor to both private clients and public authorities, providing robust and rigorous economic analysis and strategic guidance in the rapidly evolving field of competition law.
Dr. Mitja Kleczka Principal Vita In 2015, Mitja Kleczka obtained a Master’s degree in international economic consulting from the Aarhus School of Business and Social Sciences and a Master’s degree in economics from the Leibniz University Hannover. During his studies he specialized inter alia in microeconomics (particularly in industrial organization) and econometrics. In addition, he studied for some time at the Université Grenoble Alpes. After completing his education, he gained several years of consulting experience in antitrust and competition cases, notably in the quantification of cartel damages. In 2019 Mr. Kleczka earned a PhD in economics from the Free University of Brussels (VUB) with a focus on industrial organization and competition economics. His dissertation revolved around market power and merger control in strategic industries. After further research at the VUB’s Department of Applied Economics, he joined Lademann & Associates in 2021.
Johannes Hürten Manager Vita After completing his apprenticeship as an industrial management assistant and his part time education as print media manager, he worked as coordinator in an production agency. He started his studies in 2012 at the University of Hohenheim and graduated with a Master of Economics in 2017. Since 2018 is member of the Lademann & Associates team. Since then, Johannes has worked on numerous antitrust matters involving the assessment of cartel damages and the effects the abuse of market dominance. His industry experience includes among others industrial products, fast moving consumer goods, TV-advertising, retailing, and services related to the postal sector. He has consolidated an extensive set of skills in data preparation, in various statistical procedures such as regression analyses and forecasting models, in the discussion of theories of harm and in the preparation of comprehensible reports in complex issues. His colleagues appreciate his quick grasp as well as his effective and careful way of working. In addition, he published an article on the evaluation of economic analyses in the journal “Neue Zeitschrift für Kartellrecht” in 2022, which was cited in BGH LKW-III.
Dr. Hyacinthe Deliancourt Senior Consultant Vita Hyacinthe studied economics at the University of Mannheim and the University of Constance. At the same time, he studied music at the Trossingen State University of Music. His academic journey also includes study sojourns at the University of Manchester and the Aix-Marseille Université. Funded by the Swiss National Bank SNB, he completed the Swiss Doctoral Program in Economics at the Study Center Gerzensee and obtained his doctorate degree in the field of applied microeconomics at the University of St. Gallen. At the invitation of Benjamin Handel, Hyacinthe conducted research in the fields of health economics and industrial organization at the University of California Berkeley before joining Lademann & Associates. In addition to his work as an economic consultant, Hyacinthe Deliancourt is a lecturer in economics at the University of St. Gallen.
Katarina Grummel Senior Consultant Vita Katarina Grummel studied economics & law at the University of Münster and economics at the University of Düsseldorf. She completed her Master’s degree with a focus on competition economics in 2019. She also spent some time abroad in the US (California State University Fresno) as well as in France (Université de Cergy-Pontoise). Ms Grummel began her career at Lademann & Associates in 2019.
Dr. Mark Le Quement Senior Consultant Vita Mark studied Politics and Economics at the University of Copenhagen, Institut d’études Politiques in Paris and Université Catholique de Louvain in Belgium. Finally, he obtained a PhD in economics from the European University Institute in Florence in 2009. Subsequently, he was a Post Doc in Bonn and after that an associate Professor in Economics at the University of East Anglia in the UK. His field of research is in applied microeconomic theory, with a special focus on the transmission and acquisition of information in the economy and its consequences. He has published in outlets such as the Journal of Economic Theory, American Economic Journal: Micro, Journal of Public Economics, Games and Economic Behaviour. After a brief stint as an Economic Adviser at the UK Competition and Markets Authority, he recently joined Lademann and Associates.
Sina Rummelhagen Senior Consultant Vita Sina Rummelhagen studied economics at both the University of Hamburg and Aarhus University in Denmark. After successfully completing her master’s degree with a focus on microeconomics and econometrics, Sina began her consulting career in the field of competition economics at Lademann & Associates in 2013. Since then, she has gained extensive experience in the application of theoretical economic models as well as econometric methods for cartel damage estimation, mergers as well as the analysis of abuse of market power and the design of rebate systems in line with competition law. Sina has advised companies in various industries and sectors such as logistics, construction, automotive, consumer goods, agricultural products and postal services in various projects. After working several years at a well-known German competition consultancy, Sina rejoined Lademann & Associates in the summer of 2023.
Erion Shtjefanaku Senior Consultant Vita Erion Shtjefanaku studied Economics at the University of Tirana, Albania and at the University of Bonn where he focused on theoretical microeconomics and competition economics. He joined the Lademann & Associates team in the beginning of 2021.
Prof. Dr. Rainer P. Lademann Of Counsel Vita ​Rainer P Lademann is honorary professor at the University of Göttingen where he also studied business administration. There he received a PhD for his studies and his research activities on buying power and market concentration in the food retailing industry. In 1986 he founded Germany’s first company specialised in competition economics. Since then he has been involved in various merger, cartel and abuse of dominance cases in several sectors as well as in regulation cases. He has published more than 60 articles and six books on competition and strategy issues. His concept for measuring the vertical distribution of market power and market definition in food retailing contributed to impede sector specific regulations against the concentration process in the retail industry. He gave advice in the political decision process as an expert to different committees of the German Parliament as well as for die German Competition Commission (Monopolkommission). While in the 1980s and 1990s Mr Lademann had been focused on most of the bigger merger cases in the food retailing sector of Germany, the last 10 years had been affected by projects in various industries, particularly automotive, food industry, cement, insurance, network industries, paper wholesaling, chemicals, aviation and advertising markets in Germany and Europe. He has also served as an expert in litigations. Due to his university and analytical background Mr Lademann is experienced in understanding competition in different markets and in giving strategy advice in pre or post merger projects as well as in questions of distribution politics (such as in the automotive industry) or for the realignment of the market or pricing strategies of companies.
Prof. Dr. Martin A. Leroch Scientific Advisory Board Vita Martin Leroch is a Professor for Economics and Ethics & Economics at the University of Pforzheim. He holds a PhD in Economics from the University of Hamburg and a Diploma in Economics from the University of Munich. Before joining Lademann & Associates as a consultant in 2016, Martin was employed as lecturer at the Universities of Hamburg and Mainz, and as deputy professor at the University of Halle. His academic expertise covers a wide range of topics, from Global Economy over Microeconomics to Game Theory and Law & Economics. As practical competition economist he gained insights into various industries, such as automotive, mining, payment systems, system catering and track superstructures.
Kai Petersen Database & IT Manager Vita ​​After his vocational training as retail salesman, Kai Petersen studied business administration at the University of Applied Sciences in Kiel. He started working for the Gesellschaft für Wettbewerbsforschung und Handelsentwicklung in 1998 and is part of the team of Lademann & Associates since its spin-off.
Elvira Bartsch Accounting - Human Resources
Liane Kulis Management Assistant