The Expanding Patent Document: Fewer Claims, More Words, and the Drivers of Growth

Authors

• Dennis D. Crouch, University of Missouri School of Law; Patently-O

Abstract

Patent specifications have nearly quadrupled in length over the past four decades, rising from approximately 3,500 words in the early 1980s to over 13,000 words by 2025. At the same time, the average number of claims per patent has declined since peaking in 2005. Using the population of 7.6 million published patent applications from 2005 through early 2025, this Article advances a supply-side explanation for the persistent growth in specification length. The divergence between expanding specifications and contracting claims reflects a structural asymmetry in the USPTO fee schedule: excess claim fees impose a per-unit cost that visibly constrains claim counts at twenty, while the application size fee remains irrelevant to the vast majority of applications, leaving specification length effectively unconstrained. Specification growth is smooth and monotonic across two decades, with no structural break at Alice Corp. v. CLS Bank International (2014) or any other doctrinal event, and no correlation with the USPTO allowance rate despite a swing of nearly 30%. Cross-sectionally, specification length and grant rates follow an inverted-U pattern: grant rates climb from 52% for the shortest specifications to 82% at the mode before declining for the very longest applications—suggesting that excessive specification length may itself be counterproductive. The Article closes by considering whether generative AI will accelerate the trend and whether any institutional actor has the incentive or authority to arrest it.

Recommended Citation

Dennis D. Crouch, The Expanding Patent Document: Fewer Claims, More Words, and the Drivers of Growth, 33 J. Intell. Prop. L. (2026).
Available at: https://digitalcommons.law.uga.edu/jipl/vol33/iss2/3