We analyse the determinants of opposition to biotechnology and pharmaceutical patents granted by the European Patent Office between 1978–96. Opposition can be considered an early form of patent validity challenge suit. In our sample, 8.6% of the patents are attacked in opposition proceedings....

We extend theory on private–collective innovation by studying the role of exclusion rights for technology in the competition between private–collective and other innovators. We argue that private–collective innovators both pledge their own and invest in orphan exclusion rights for...