An Empirical Look at Software Patents

"Software patents have grown rapidly in number and now comprise 15% of all patents. They are acquired primarily by large manufacturing firms in industries known for strategic patenting; only 5% belong to software publishers. The very large increase in software patent propensity over time is not adequately explained by changes in R&D investments, employment of computer programmers, or productivity growth. The residual increase in software patent propensity is consistent with a sizeable increase in the cost effectiveness of software patents during the 1990s, perhaps arising from changes in the application of patent law to computer software." Copyright 2007, The Author(s) Journal Compilation (c) 2007 Blackwell Publishing.