Lemley, Mark A., and Carl Shapiro. 2005. “Probabilistic Patents." Journal of Economic Perspectives, 19(2): 75-98. DOI: 10.1257/0895330054048650; URL: http://www.aeaweb.org/articles.php?doi=10.1257/0895330054048650
==Notes by yinung==
多年前就知道 Carl Shapiro 轉往研究 IP 相關之經濟議題, 不過卻到今日才略領其大意…
為何稱做 “Probabilistic" patents
Virtually all property rights contain some element of uncertainty…. There are two fundamental dimensions of uncertainty:
1) uncertainty about the commercial significance of the invention being patented, and
2) uncertainty about the validity and scope of the legal right being granted.
(p.81)…Many patent applications, and indeed patents themselves, are like lottery tickets. Inventors who are uncertain of the commercial significance…Two of the most common practices used by patentees to increase their chances of winning the patent lottery are continuations and a proliferation of closely related patents… increasing the chance that
their patents will cover technology that becomes widely adopted by market participants.
Patent 訴訟不見得不好, 因為有外部性
… because litigating patent disputes to completion tends to generate positive externalities, by clarifying the limits of patent protection if the patent is upheld or encouraging wider use of the innovation if the patent is invalidated.
為何大部份的 patent 的價值都很低, 但申請數量卻眾多?
1. 申請者不確定哪些會有價值 (Scherer, 2001; Denton and Heald, 2004)
2. 申請者不知道其價值 (Rivette and Kline, 2000)
3. 數量多有利於財務操作和增加市場評價 (Lemley, 2000; Hall, Jaffe and Trajtenberg, 2005)
4. 當做 signaling mechanisms (Long, 2002)
5. 防禦性功能 “defensive” use of patents to deter others from suing (Hall and Ziedonis, 2001; Lemley, 2001)
6. 綁在 patent portfolio 中 (Parchomovsky and Wagner, 2004)
Why do inventors file for many patents that turn out to have little or no value? Surely part of the reason is that patent applicants do not know which patents will be valuable and which will be worthless (Scherer, 2001; Denton and Heald, 2004). But other explanations have been offered: a failure to understand the value of patents (Rivette and Kline, 2000); the use of patents to obtain financing and boost market valuation (Lemley, 2000; Hall, Jaffe and Trajtenberg, 2005); the use of patents as signaling mechanisms (Long, 2002); and the “defensive” use of patents to deter others from suing (Hall and Ziedonis, 2001; Lemley, 2001). Even individually weak patents might have value as part of a large patent portfolio, because the portfolio can be licensed as a block or can serve to deter lawsuits (Parchomovsky and Wagner, 2004).
專利入場券 patent ticket
… “patent thicket," in which hundreds of patents can apply to a single product (Shapiro, 2001; FTC, 2003). …One way to cut through the patent thicket is for incumbents with extensive patent portfolios to enter into broad cross-licenses (that is, exchanges of roughly symmetric patent positions) to “clear” the thicket.
Without such cross-licenses, the result is inefficient “royalty stacking,” in which a manufacturer without its own patent portfolio must pay royalties to a number of separate companies.
申請者比較會有個別資訊 …applicants appear to have considerable private information at an early stage about the likely value of at least some of their patents. … Allison, Lemley, Moore and Trunkey (2004) find… most significant predictors of ultimate value observable to researchers are the industry, the number of prior art references, the number of claims in the patent and the time invested in prosecution of the patent.
使專利失效 invalidating a patent 會有正外部性 (即會 under-supplied), 因此被控之廠商通常會尋求和解, 而不是興訟
… challenges to patents are undersupplied (Gilbert, 2004; Farrell and Merges, 2004)
The key insight is that invalidating a patent generates significant positive externalities, and activities that generate positive externalities are undersupplied. There are very strong reasons to believe that challenges to patents are undersupplied (Gilbert, 2004; Farrell and Merges, 2004).
Economists often assume that a patent gives its owner a well-defined legal right to exclude others from practicing the invention described in the patent. In practice, however, the rights afforded to patent holders are highly uncertain. Under patent law, a patent is no guarantee of exclusion but more precisely a legal right to try to exclude. Since only 0.1% of all patents are litigated to trial, and since nearly half of fully litigated patents are declared invalid, this distinction is critical to understanding the economic impact of patents. The growing recognition among economists and legal scholars that patents are probabilistic property rights has significant implications for our understanding of patents in four important areas: (1) reform of the system by which patents are granted; (2) the legal treatment of patents in litigation; (3) the incentives of patent holders and alleged infringers to settle their disputes through licensing or cross-licensing agreements rather than litigate them to completion; and (4) the antitrust limits on agreements between rivals that settle actual or threatened patent litigation.