Continuing patent applications at the USPTO
研究了美国专利商标局继续专利申请的用途，发现申请人利用它来保持审查开放、调整专利范围，从而提升专利价值，尤其在不确定性和高价值技术领域更常见。
Despite their growing importance for firm innovation strategy and frequent appearance in U.S. patent policy debates, how continuing patent applications are used remains unclear. Turn-of-the-century reforms strongly limited opportunities to extend patent term and surprise competitors, but continuing applications have steadily risen since. We argue that they retain a subtle use, as applicants can file continuations to keep prosecution open and change patent scope after locking in gains with the initial patent. We document a sharp drop in parent abandonment and rise in continuations per original patent after the reforms. Continuing applications are more privately valuable than original patents, are filed in more uncertain contexts, for higher value technologies, by more strategic applicants, and react strongly to the notice of allowance. The evidence supports a current strategic use of continuing applications to craft claims over time.