Vopel, Katrin; Scherer, Frederic M.; Narin, Francis; … - Zentrum für Europäische Wirtschaftsforschung (ZEW) - 1997
Through a survey, economic value estimates were obtained on 962 inventions made in the United States and Germany and on … which German patent renewal fees were paid to full-term expiration in 1995. A search of subsequent U.S. and German patents … allowed to expire before their full term. The higher an invention?s economic value estimate was, the more the relevant patent …