Right Sized Patents

Dennis Crouch

Many progressive policies focus on reducing disparities (income, wealth, education, and opportunities) that reflect some social injustice between those at the top and those at the bottom of our social spectrum. Conservatives often recognize the gaps but disagree about whether the result qualifies as injustice as well as about government’s role in redistribution.

Patent policy is often easier to implement than social policy (especially compared with other property law changes) because a new generation of patents emerges every twenty years and the old generation does not hang-around protecting and directing wealth but instead melds into the Soylent of the public domain.

In some ways though, patents are bucking the social trend and becoming more standardized and less diverse – at least by some outward measurements such as document size, claims per patent, and prosecution pendency.

Standard deviation is the most common measure of spread or dispersion of a statistic across a population. A population with a wider spread and more outliers will have a greater standard deviation.  For patent claims, this measure of spread has been dropping steadily for the past decade.  The first chart below shows the standard deviation of patent claim count for issued US utility patents grouped by year of issuance.

StdevClaimCountPatentlyo

The reduction in variance has been accompanied by a drop in the average number of claims per utility patent as shown in the next chart (note the axis break).

AvgClaimsPerPatent

My working hypothesis is that there are three primary drivers for the drop in claims-per-patent and all three also serve to (partially) explain the drop in spread.  These drivers: (1) a substantial increase in fees for filing more than 20 claims-per-patent that was put into place in 2004 and has continued to rise; (2) a suggested (but not confirmed) rise in restriction requirements for patents with more than 20 claims; and (3) a decrease in patent valuation leaving patentees less willing to support the higher cost of a large number of claims.  (As an aside, reasons (1) and (2) may also helping to dive the continued rise in re-filing.)

At the same time, however, another interesting trend is reducing the spread: there are fewer “small” patents with only 1-5 claims. Thus, the trend is a reduction of both small and mega patents (as measured by claim count) with a proportional increase in the middle with ‘average sized patents’.   The final chart below provides some further context to these statements.

PatentClaimCounts

The time series chart groups each year’s patents into a set of bands according to the number of issued claims.  As a savvy chart reader could surmise, the percentage of patents with 1-5 claims has dropped since 2002 as has the percentage of patents with >30 claims.  Those reductions were accompanied by a proportional rise in patents with 16-20 claims.  Time will tell whether this shift also leads to a more just society.