The German entrepreneurial index (GEX®): a primer on an ownership-based style index in Germany

Recent research indicates that the majority of listed firms in Germany (and also in many other countries around the world) have a dominant owner rather than being widely-held. Hence, owner-dominated firms comprise an important subset of listed companies. This article introduces the concept of an ownership-based style index of listed firms in Germany, the German Entrepreneurial Index (GEX®). Introduced in 2005, the GEX® represents recently listed, ownerdominated firms in the German Prime Standard. We review the theoretical foundation and the index construction of the GEX®. In addition, we provide an overview of its development and performance between index inception and end of 2008 and relate this to properties of the German financial market. Finally, we conclude with a critical outlook for the index future against the background of recent developments.