Since the U.S. Supreme Court’s landmark decision, Markman v. Westview Instruments, Inc., courts have employed a textualist approach when construing patent claims. Claim construction has been held to be purely a matter of law, which leaves no room for deference when the construction is reconsidered on appellate review. But as argued in this article, patent claims are a unique type of legal text, and cannot simply be analogized to statutes or contracts, which courts and scholars occasionally attempt to do. Taking lessons from the general legal theory of interpretation, the textualist approach should only be a starting point for the interpretation of patents, rather than an all-encompassing approach. By adapting and using a range of theories of legal interpretation outside the patent sphere, we can find an approach to patent claim construction that more consistently results in satisfactory constructions. This may, for example, include consideration of fact-intensive inquiries such as an inventor’s intention and public policy. As a corollary, an expansive jurisprudential approach to patent claim construction calls into question current patent doctrine concerning the standard of review—should claim construction really be subject to de novo review?
Christian E. Mammen, Patent Claim Construction As a Form of Legal Interpretation, 12 J. Marshall Rev. Intell. Prop. L. 40 (2012)