Theon vierkant Theon van Dijk is the founder of Lexonomics and has more than 20 years experience in competition cases before the EU Commission as well as national competition authorities in the Netherlands, Belgium, Germany, France and the United Kingdom. He has advised firms in various sectors in more than 100 procedures relating to mergers and acquisitions, abuse of dominance, cartels, vertical relationships, horizontal cooperation agreements, state aid en licensing of intellectual property. He has prepared economic reports for parties in litigation cases and has acted as economic expert.


In addition to private parties, Theon has extensive experience in assisting competition authorities and regulators with the assessment of competitive effects of concentrations and certain business practices. He has carried out economic background studies for, amongst others, the Dutch Ministry of Economic Affairs, the NMa, the OPTA and Directorate General Internal Affairs of the European Commission.


Theon holds a PhD in Industrial Organisation of Maastricht University and has been a postdoctoral fellow at the Institut d’Économie Industrielle, Université de Toulouse. He has various international academic publications in the area of competition policy and intellectual property in, amongst others, European Competition Law ReviewEuropean Economic ReviewJournal of Industrial EconomicsResearch PolicyJournal of Network IndustriesEconomics Letters, and in Dutch journals such as Economisch Statistische BerichtenMarkt & Mededinging, Tijdschrift Privatisering and Actualiteiten Mededingingsrecht.


Theon van Dijk has been a board member of the Dutch Association of Competition Law from 2007 to 2013. He is mentioned in recent International Who is Who lists of competition economists and in recent Expert Guides to the World’s Leading Competition and Antitrust Lawyers/Economists by the Legal Media Group.


From 2013 to 2015 Theon was Chief Economist of the European Patent Office in Munich.


Paul website foto

Dr Paul de Bijl can be reached at Radicand Economics (












jonas website

Jonas Rosenstok works together with Lexonomics since September 2007. Before that he worked with the Dutch telecommunications and post regulator OPTA for almost 3 years, where he was member of the Economic Analysis Team, carried out economic analyses in de broadcast sector and set up a structural market monitoring system. Jonas was also seconded with the merger control unit of the Dutch competition authority NMa.


Jonas studied Economics at Maastricht University, with a Minor in European Studies. He won the ENCORE Master Thesis Prize for his work on the efficacy of the Dutch leniency programme.