In 2016, De Jong (1987) defended his PhD thesis about Precautionary Duties in Tort Law. His supervisor was prof. A.L.M. Keirse. In 2014 he was awarded the publication price of the Dutch Society for Civil Law, for an article on the relationship between scientific uncertainty and tort law. After his PhD graduation, until 2017, he was a postdoc researcher at Ucall. He then received an NWO-Rubicon grant, which financed a researched stay at the Institute of European and Comparative Law van Oxford University, from April 2017 to April 2018. During that period he also was a research affiliate at Corpus Christi College of Oxford University. In his research, he addressed the role of civil judges in risk regulation. After his stay at Oxford, he returned as an Associate Professor to Utrecht University. In 2020 he received an Early Career Partnership of the Royal Netherlands Academy of Arts and Sciences in order to set up his research into complexity and the law of obligations. in order to set up his research into complexity and the law of obligations. As of 1 September 2020 he is appointed as Professor of Private Law.