Over the course of the last week, I’ve come across two blog posts, via my twitter feed, that show opposite views on patent litigation. The first takes the position that patent troll litigation is rampant and stifling innovation, especially for startups. The title, “Numbers Don’t Lie: Patent Trolls are a Plague” sums up the author’s position nicely. However, the piece doesn’t paint a very comprehensive picture.
The numbers referred to are those based on a survey by Colleen Chien of Santa Clara University – School of Law. Prof. Chien notes that 40% of respondents stated that troll activities had had a significant impact on the startup’s operations. However, the fact that patents are asserted against emerging businesses more often than others shouldn’t come as a surprise. After all, if a company is arguably infringing a patent as part of its core business, it would be expected that the issue would come up earlier in the company life cycle. These numbers could be skewed relative to the economy as a whole.
The second article takes another tack as you can see from the equally suggestive title, “The ‘Patent Litigation Explosion’ Canard.” As you can guess, the author, Prof. Adam Mossoff, disagrees with the idea that there is a “Patent Litigation Explosion” going on. This piece discusses patent litigation rates (measured as a percentage of issued patents litigated). From 1790 to 1860 the rate averages 1.65%. From 2000-2009, it was 1.5%.
I’m inclined to think the litigation rates over time to be a better indicator of the growth of patent litigation than a survey of startups. To be honest, I was skeptical of the litigation rates, not that they are inaccurate, but they may not be very meaningful if the number of patents issued relative to GDP has gone up. My assumption was that the number of patents issued per billion dollars of GDP would have grown and that the a constant litigation rate would actually mean an overall increase in patent litigation relative to GDP. That assumption was wrong.
First I looked to the USPTO data regarding patents issued. Here is a chart for patents issued each year from 1963 to 2011.

The “ups” and “downs” unsurprisingly correlate to the general state of the economy as fewer patents issue during and after economic downturns. However, I was interested in the number of patents issued per billion dollars in GDP. I used real GDP data (GDP adjusted for inflation) and the number of utility patents issued for each year from 1963 to 2011. So, I simply divided the number of patents issued in a given year by the inflation adjusted GDP that year. The following chart shows what I found:

While there is a lot of variation, the overall trend appears relatively flat. The average number of patents issued per billion dollars of GDP from 1963 to 2011 was 13.00, and a significant portion of the last decade was below that. Accordingly, the litigation rates referenced by Prof. Mossoff are informative and it appears that there has not been a significant increase in patent litigation, relative to GDP.
Of course, this is only part of the story. Calculating litigation rates as a function of the number of patents issued in a particular year doesn’t necessarily correlate to the number of patents in force (i.e. issued and with all relevant maintenance fees paid that have not yet expired) for that year, but it is, perhaps, a leading indicator of the number of patents that will be in-force in years to come. Such a calculation, however, is easier to make and is likely a reasonable starting point.
Another issue is that these numbers doesn’t tell us the economic impact of patent litigation. While the number of cases relative to GDP is steady, the average price tag (damages, attorney’s fees, etc) associated with a patent litigation may have grown relative to GDP, or there may have been a significant increase in licenses entered before a complaint is filed. However, I haven’t seen any data to show that either of those things has happened.