Prof. Dr Dieter Fensel passed away in Innsbruck on 29 December 2024 after a long illness. Dieter Fensel was born on 10 October 1960 in Nuremberg, Germany. After attending school in and around Nuremberg, he studied mathematics at the Free University of Berlin. He also earned two master's degrees: One in Sociology at the Free University of Berlin and one in Computer Science at the Technical University of Berlin.
Dieter began his extraordinary academic career at the University of Karlsruhe, where he received his doctorate in 1993 under the supervision of Prof Dr Rudi Studer. He later completed his habilitation, also in Karlsruhe, and was honoured with the Carl Adam Petri Prize for his outstanding work. Between 1989 and 1999, he conducted research at the University of Karlsruhe and completed a two-year research stay at the University of Amsterdam (UvA), funded by a scholarship from the German Research Foundation.
In 1999, Dieter Fensel moved to Amsterdam to take up a position as Associate Professor at the Vrije Universiteit Amsterdam (VU). In 2002 he became a full professor at the University of Innsbruck and in 2003 at the National University of Ireland in Galway. During this time, he founded the Digital Enterprise Research Institute (DERI) and established it in both Innsbruck and Galway. The Innsbruck centre was later renamed the Semantic Technology Institute (STI) Innsbruck, which he headed until his death.
As a pioneer in the field of semantic technologies, Dieter Fensel was one of the most influential scientists of his generation. He researched the development of knowledge representation and formal languages that function in decentralised and dynamic information environments such as the web. This work laid the foundation for what later became known as the "Semantic Web".
He recognised early on the importance of a global ecosystem that was necessary for the success of this emerging field of research. With great commitment, he led initiatives that contributed significantly to the development of this ecosystem. These included the co-founding of the STI International Association, a network of research organisations and industry, as well as the conception of a special Semantic Web Summer School to train future leaders. He was co-founder of two important conferences: The Extended Semantic Web Conference (ESWC) and the International Semantic Web Conference (ISWC). He successfully raised funds to advance the Semantic Web research agenda and to support the broader ecosystem.
His research has also had a significant impact on the local economy, notably through the founding of start-ups such as seekda and Onlim, as well as the Tourism Fast Forward congress, which he co-founded.
Prof Dr Dieter Fensel leaves behind an extraordinary legacy. There is hardly a person in the world of the semantic web, ontologies or knowledge graphs whose path did not cross his - be it as a student, colleague, employee or mentee. His intellectual curiosity, his passion for science and his pursuit of effective solutions have shaped countless personalities and careers.
In recent years, Dieter Fensel has devoted himself with great enthusiasm to his hobby of exploring the universe. We will meet him there again one day - among galaxies, stars and planets. And, as always, he will show us the way.
We feel deeply honoured to have worked with him for many years and to have learned from him. Our deepest sympathy goes out to his sister, his daughter, his nephews and his entire family.
Thank you, Dieter, for your mentorship, vision and generosity. Your legacy will live on. Rest in peace.
written by Umutcan Serles, PhD, on behalf of Prof Dr John Domingue, Prof Dr Anna Fensel, Prof Dr Andreas Harth, Elias Kerle, PhD, Prof Dr Elena Simperl, Prof Dr Rudi Studer, Dr Ioan Toma, Dipl.-Ing. Alexander Wahler and numerous other current and former STI and DERI colleagues