Rosenstok Economics provides thought-through advice and support in the field of competition and regulation.

Since August 2007, Rosenstok Economics has advised and supported clients in a large number of sectors including Healthcare, Pharmaceutical, Electronic Communications, Postal, Electronics, Consumer Lifestyle, Entertainment, Agriculture, Automotive and the list goes on.

From September 2013 to May 2016, Jonas worked in the board of directors of Haydom Lutheran Hospital in Tanzania. Prior to establishing Rosenstok Economics, Jonas worked for the Dutch telecommunications and post regulator, the Dutch competition authority and the competition directorate of the Dutch ministry of economic affairs.

From 2016 onwards, Jonas has shifted his focus away from competition economics and towards policy and practice in the public domain, mainly focused on healthcare. Jonas now operates under the name Contragewicht.

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.