摘要：Presenting the first comprehensive study of evergreening, this article examines the extent to which evergreening behavior—which can be defined as artificially extending the protection cliff—may contribute to the problem. The author analyses all drugs on the market between 2005 and 2015, combing through 60,000 data points to examine every instance in which a company added a new patent or exclusivity. The results show a startling departure from the classic conceptualization of intellectual property protection for pharmaceuticals. Rather than creating new medicines, pharmaceutical companies are largely recycling and repurposing old ones. Specifically, 78% of the drugs associated with new patents were not new drugs, but existing ones, and extending protection is particularly pronounced among blockbuster drugs. Once companies start down the road of extending protection, they show a tendency to return to the well, with the majority adding more than one extension and 50% becoming serial offenders. The problem is growing across time.
