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The Reporting Gap on the Patent Gender Gap

Rosie the Riveter, demonstrating the strength of working women.

Measuring innovation by women on the basis of science and engineering patents assigned to women is tricky; three reports on the topic agree someone on the trend of women receiving more such patents, but they can't seem to agree on the specifics.

Credit: Global Patent Solutions

Whether or not women are making progress in assigned patents in the sciences and engineering, one measure of innovation, remains unclear. Three reports on the subject cannot seem to agree; they use different methods and data, and examine different time intervals of patent applications, assignments, commercialization, and probability of commercialization.

This May, the journal Research Policy published "Why are women underrepresented amongst patentees?" by economists Jennifer Hunt, Hannah Herman, Jean-Philippe Grant, and David J. Munro. Their previous working paper, commissioned by the National Bureau of Economic Research, was entitled, "Why Don't Women Patent?" and began circulating in March 2012.

Hunt et al investigated holders of patents and found that just 7.5 percent of them are women, and just 5.5 percent of those holding commercialized patents are women.

In trying to explain why this is so, the researchers found that only 7 percent of the gender gap in commercialized patents may be attributed to women's lower probability of having a science or engineering degree, because women with such degrees are barely more likely to patent than women who lack them. The most significant determinant is women's underrepresentation in patent-intensive fields, the authors say, especially in electrical and mechanical engineering, and in patent-intensive jobs, especially development and design. The authors claim the patenting rate of women with science and engineering degrees is "sufficiently low" that increasing women's representation in science and engineering generally "would have little effect absent other changes."

Hunt, a professor of economics at Rutgers University, elaborates, "It is not enough to send women in to science and engineering in general" in order to bring up their rate of patenting. "They have to be in the patent-intensive parts, which are physical science and engineering, and of those, the problem lies more with engineering, because that is where the underrepresentation is much worse."

In the recently published paper, Hunt and her colleagues write, "Eliminating the patenting shortfall of female holders of science and engineering degrees would increase GDP per capita by 2.7 percent." That is an approximation, Hunt explains, which she derived from a secondary result in another paper that included data on countries over time, and then looked for what is correlated with GDP. "The explanatory variables included employment (which is why the effect of other variables can be considered as the effect on GDP per capita) and included patents in that country," she says, "So from that paper I got the link between patents and GDP per capita, then I multiplied that by the increase in patents due to immigrants in the 1990s." The value of patents does vary widely, she concedes, but this "reflects the average value and we generally deal with average effects."

Women's Patents Soaring?

Another report, "Intellectual Property and Women Entrepreneurs", released in February 2012 by the federal advisory National Women's Business Council (NWBC), states that "the number of women awarded patents has soared over the last several decades."

The report, authored by Nazeer Ahmed, CEO of Delixus, Inc., a market research, advanced analytics, and process automation company based in Concord, CA, with associates Hena Kauser, Maimoona Ahmed, Lavetta Cross, Akbar Ahmed, Don Mironov, and Afshan Hai, found a surging number of patents have been obtained by women in recent years. The NWBC study found with the largest spike of women patenting in 2010, when 22,984 patents were granted to women, a 35-percent jump over the previous year (the study also said men obtained 121,257 patents in 2010, a jump of 28 percent from 2009 levels). In 2009, women received 17,061 patents, a 4.5-percent increase over the 16,321 issued in 2008, whereas men obtained 94,850 patents in 2009, a 4-percent hike over the 91,342 patents they obtained in 2008, the report said.

The NWBC study said the top categories for women-held patents were chemistry, bio-affecting drugs, semiconductor device manufacturing, and furnishings. The biggest increases in women-obtained patents came in data processing, electrical computers and digital processing systems, and surgery. Overall, according to the NWBC study, women received 16 percent of all patents granted in 2010, compared to the 14 percent of patents they received a decade earlier. In contrast, in 1990 they received only 8 percent (4,712) of 56,552 patents granted, according to NWBC.

The third report, a 2010 working paper on women and African American patentees, "The Idea Gap in Pink and Black," currently under review at Science, addresses gender, as well as racial, representation among patentees. Its authors are economists Lisa D. Cook, who has a joint appointment with the departments of Economics, and Economic and International Relations, at Michigan State University, and Chaleampong Kongcharoen, also of Michigan State. They are the first to examine African American representation among patentees.

Cook and Kongcharoen found 169,061 U.S. patents granted to women between 1975 and 2008, nearly 5 percent of the 3,596,116 utility patents the USPTO says were granted during that period. During the same period, the researchers found just 1,167 patents had been granted to African Americans. "U.S. women inventors were granted between 17 patents per million between 1980 and 1989 and 56 patents per million annually between 1990 and 1999," they write. "On average, women inventors participate more actively in the drugs and medical field than other U.S. inventors." They find this consistent with relatively higher shares of women receiving life sciences degrees and relatively lower shares of women receiving engineering degrees since 1970. "The share of electrical inventions among women's patents is six percentage points lower than that of U.S. inventors between 1975 and 2008. The share of chemical patents for female inventors drops slightly over time but is still higher than for that of U.S. inventors.""

Cook concurs with Hunt et al, in that she also questions whether the growing number of women obtaining advanced degrees translates directly into more women receiving patents on their work. "It doesn't seem to be the case" that the growth in women receiving advanced degrees is "turning into innovation," she says; "I was struck that this is true for women and African Americans. The numbers (of patents granted to women) are disproportionately small."

Why the disparity in these reports' findings? For one thing, because the U.S. Patent and Trademark Office (USPTO) does not ask patent applicants' genders, the researchers had to come up with ways to derive gender data for patent applicants.

The NWBC massaged USPTO data, using software to match the names provided on each patent submission with lists of common female names compiled by the U.S. Census Bureau and Social Security Administration.

Hunt et al. drew on the National Science Foundation's 2003 National Survey of College Graduates (NSCG). Part of a longitudinal survey conducted every other year since the 1970s, the NSCG provides data useful to understanding the relationship between college education and career opportunities. The 2003 edition of the study in seperate questions asked college graduates their gender, and whether they had been named as inventor on any patent application; if they had, they were asked on how many applications they had been listed, and how many had been granted.

Hunt, however, says the NWBC study used USPTO data improperly. "Their findings are completely contradictory. I did not find their study informative," she says. "Given talk of accelerating increases and their claim that patents by women rose 35 percent from 2009 to 2010 (totally implausible), it is unconvincing. They admit themselves their data on patent applications appear to have a severe problem. But their data on patents granted seems to be at a completely different level and a different time pattern from the aggregate data from the USPTO web site." According to Hunt, in 2010 the NWBC only found 120,000 patents granted to both men and women, but according to the USPTO for U.S.-based utility patents, that number should be about 250,000. "Unlike in the report's data, patents don't jump 35 percent from 2009 to 2010," she says.

According to Delixus'  Ahmed, who was technical director of the NWBC project, Hunt's claim that he admits the NWBC data on patent applications are problematic because it "disregards the fact that the NWBC report uses the original USPTO data set as input, which is the single highest-quality data source about US patent applications and grants." Furthermore, he says, "Such a claim is not supported by the NWBC report." Hunt's statement regarding 120,000 vs. 250,000 patents granted to both genders in 2010 "conveniently disregards the report's clear documentation that the USPTO data set for 2010 was a partial data set," says Ahmed.

The NWBC study is the first to leverage Big Data technologies to analyze all of the original USPTO patent records from 1975 to 2010, he says. These techniques eliminate the use of sampling techniques, which have until now been required when studying this important topic, and "therefore improved data input quality by eliminating sampling biases, among other biases, in the input data set," Ahmed says. He is confident the report is "correct and accurate," calling it "path-breaking," and welcomes Hunt to "reprocess the original USPTO data to verify our results."

As for the NSF's NSCG surveys, researchers may not be able to reconcile data differences concerning gender disparity in intellectual property after 2003 because in 2006, 2008, and 2010, the survey did not ask whether respondents had been named as an inventor on an application for a U.S. patent. Cook says the impact of the absence of the question "is devastating" to gender and intellectual property research. She adds, "We will have to find a way to get this information otherwise, and it is not clear where. This is a big survey, and a number of people in this field depend on it."

According to NSF National Center for Science and Engineering Statistics senior advisor Nirmala Kannankutty, the question on patents was not asked in subsequent NSCG surveys "because there is a small incidence of patenting aside from doctorates, and this was a question that was not meant to be asked in every round, but only periodically." Survey statistician John Finamore says there are plans to review and potentially update the 2015 survey content.

"The tradeoff is having more information about a subset of inventors rather than having more information about patents in the aggregate," Cook says, "so the NWBC has a lot less detailed information, but they are able to identify trends in patenting and commercialization."

Yet, like the NWBC, she finds that women are doing better in the patent realm. "Women are closing the gap, clearly, but women still patent one order of magnitude less than the overall patenting population," Cook says.

Karen A. Frenkel writes about science and technology and lives in New York City.


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