Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
We analyse how patent thickets affect entry into patenting. A model of entry into patenting that allows for variation in technological opportunity, technological complexity and the extent of patent thickets is developed and analysed. Using UK data we then show that patent thickets are associated with a reduction of first time patenting in a technology controlling for the level of technological complexity and opportunity. Technologies characterized by more technological complexity and opportunity attract more entry into patenting. Our evidence indicates that patent thickets raise entry costs, which leads to less entry into technologies regardless of a firm’s size.