The entire conclusion is below. See also Keith Sawyer's post, Do Patents Increase Innovation?, who note: "In 1999, for example, the total profits from patents in all U.S. public firms (excluding pharma) was about $3 billion, but their litigation costs associated with those patents were a whopping $12 billion!"
The historical evidence, the cross-country evidence, the evidence from economic experiments and estimates of the net benefits of patents all point to a marked difference between the economic importance of general property rights and the economic importance of patents or intellectual property rights more generally. With the cross-country studies in particular, the quality of general property rights institutions has a substantial direct effect on economic growth. Using the *same* methodology and in the *same* studies, intellectual property rights have at best only a weak and indirect effect on economic growth.
The research also suggests a reason why patents differ from general property rights in motivating economic growth overall: the positive effects of patents appear to be highly contingent. Differences in technology and industry seem to matter a lot for twentieth century R&D managers and also for the innovative performance of nineteenth century world's fair exhibitors. Some results from the cross-country studies suggest that less developed countries have a harder time realizing benefits from patents or that countries that participate actively in international trade may benefit more.
Some of these differences arise because of differences in the relative costs and effectiveness of alternatives to patents. Patents may contribute more to economic growth in the pharmaceutical industry than they contribute in electronics industries because the latter can more effectively earn returns on innovation through lead time advantage, sales of complementary products and services, etc. Other differences may arise because of subtle differences in patent institutions. During the nineteenth century, the US patent institutions performed differently (and perhaps better) than their British counterparts. Patents are likely to work better in the pharmaceutical industry because patents on chemical entities have much sharper boundaries than, for example, patents on software.
Of course, the economic effectiveness of all forms of property depends on details of the supporting institutions this is evident from the disparate growth paths of Soviet Bloc economies. But the economic effectiveness of patents may be much more sensitive to the details of the relevant institutions than are general property rights. Perhaps this is because patent law may be much more specialized, complex and sophisticated than, say, real property law and, so, effective institutions may be more difficult to develop and maintain.
In any case, the empirical economic evidence strongly rejects simplistic arguments that patents universally spur innovation and economic growth. The direct comparison of estimated net incentives suggests that for public firms in most industries today, patents may actually discourage investment in innovation.
