Stefan received his PhD in 2015 from the Technische Universität of Darmstadt, Germany, where he worked in the Group of Harald Kolmar in the field of protein engineering of non-canonical antibodies. During his PhD he spent some time at Scripps Institute, La Jolla (USA) working in the lab of Vaughn Smider on ultra-long CDR-H3 cow antibodies. After his Post Doc at Sanofi, Stefan joined Merck KGaA (EMD Serono) in 2016 as Senior Scientist. At the moment, he works as Associate Director at Merck KGaA, Germany, in the Department Protein Engineering and Antibody Technologies (PEAT).