The continuations procedure within the U.S. patent system has been criticized for enabling firms to manipulate the … patent review process for strategic purposes. Changes during the 1990s in patent procedures affected the incentives of … by R&D-intensive, small firms that patent heavily, and are more common in chemical and biological technologies. Patents …

pharmaceutical incumbents just before they lose patent protection. The approach involves looking at a cross-section of markets and … of drugs which lost patent protection between 1986 and 1992. Among the findings consistent with an entry deterrence … advertising immediately prior to patent expiration. …