WORKING PAPER · NO. 2020-133

COVID-19 Shifted Patent Applications toward
Technologies that Support Working from Home
Nicholas Bloom, Steven J. Davis, and Yulia Zhestkova
JANUARY 2021

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COVID-19 Shifted Patent Applications toward
Technologies that Support Working from Home
Nicholas Bloom,1 Steven J. Davis2 and Zulia Zhestkova3
8 January 2021

Abstract: We examine the text content of U.S. patent applications, identifying those that advancetechnologies in support of video conferencing, telecommuting, remote interactivity, and working
from home (collectively, WFH). The share of new patent applications that advance WFHtechnologies more than doubles from January to September of 2020, greatly surpassing its previous
peak, and following an upward trajectory since the onset of the pandemic. This evidence suggeststhat (re-)directed technical change in reaction to COVID-19 will raise the quality and efficiencyof remote work, thereby reinforcing a shift to working from home even after the pandemic ends.

Contacts: nbloom@stanford.edu, Steven.Davis@chicagobooth.edu, yzhestkova@uchicago.edu,JEL Nos.: O3, J21

Keywords: directed technical change, patents, COVID-19, coronavirus, working from home,remote interactivity, text analysis

Acknowledgements: We thank the University of Chicago Booth School of Business for financial
support.

1 Stanford University
2 University of Chicago Booth School of Business and Hoover Institution
3 University of Chicago

COVID-19 triggered a massive shift to working from home. In the spring of 2020,
American workers supplied roughly half of paid labor services from home.4 According to survey
evidence in Barrero et al. (2020), 23 percent of all full work days will be supplied from home after
the pandemic ends, as compared to just 5 percent in 2017-18. Stock prices also reflect the shift toworking from home. For example, Papanikolaou and Schmidt (2020) report daily equity returns in2020 for firms sorted by share of employees able to work remotely. From 14 February 2020 to 15June, the cumulative return differential between the top and bottom quartiles is 19.4 percentage
points, with most of the differential emerging by mid-March. Similarly, Pagano et al. (2020) findmuch higher returns in the wake of COVID-19 at “resilient” firms, as measured by the ability of
their employees to perform jobs at home and without interactions in physical proximity.
These observations prompt us to ask whether COVID-19 has also shifted the direction of
innovation toward technologies that support video conferencing, telecommuting, remoteinteractivity, and working from home (collectively, WFH). The economic reasoning is simple:
When remote work becomes a bigger share of all work, the incentives to advance technologies that
support WFH become stronger. Likewise, Acemoglu (1998) stresses that a high proportion ofskilled workers in the labor force implies a large market size for skill-complementary technologies,
creating incentives for skill-biased technical change. Motivated by this type of reasoning, weassess how forcefully the direction of technical change responds to a large, sudden, surprise shift
in working arrangements.
Specifically, we use human-guided automated readings of U.S. patent applications,
identifying the ones that advance WFH technologies. We start with the raw XML files of new

4 See Barrero et al. (forthcoming), Bick et al. (2020), Brynjolfsson et al. (2020), and Ozimek,2020.
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patent applications, which are published by the United States Patent and Trademark Office(USPTO) every Thursday. These files include the patent application date (filing date), publication
date, application ID, inventor name, assignee (entity that owns the patent), patent class, title, andfull text of the invention description. We examine the content of the invention descriptions toidentify patent applications that advance WFH technologies. Our analysis sample contains all
patent applications published from 7 January 2010 through 24 December 2020, which coversfilings from 1 January 2010 to 11 September 2020. There are about 3.6 million patent applications
in our dataset, 20,907 of which pertain to WFH technologies according to our classification
algorithm described below.
As a first step, we construct a dictionary of terms that pertain to WFH technologies. To doso, we manually reviewed twenty articles about “working from home” “working from hometechnologies,” “remote work tools” and the like drawn from online encyclopedias, newspapers,
tech-oriented media, and popular blog posts. Based on our review, we created our dictionary ofWFH terms: telecommuting, telework, teleworking, working from home, mobile work,
remote work, flexible workplace, work from home, mobile working, remote working,work remotely, working remotely, remote workplace, telecommuter, teleworker, home-sourced
worker, home-sourced employee, work-at-home, work at home, telecommuting specialist, nomadicworker, nomadic employee, work-from-home, work-from-anywhere, video conference, videoconferencing, virtual office, distance work, flexible work, virtual work, virtual office, virtual
employee, home office, home-based office, home-based work, work from anywhere, working
from anywhere, work-from-anywhere, digital workplace, video chat, video call, teleconference,teleconferencing, working from a remote location, work from a remote location.

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Second, we execute computer-automated readings of the patent application texts thatsummarize the invention and describe its potential applications. If the text contains one or moreterms in the dictionary above, we regard the patent application as one that advances WFH
technologies. Similar results obtain when requiring the text to contain two or dictionary terms.
Sample titles (assignee, filing date) of patent applications selected by our WFHclassification include “Method and System for Elevating a Phone Call into a Video Conferencing
Session” (Zoom Video Communications, Inc., 20 March 2020), “Optimizing Video Conferencing
Using Contextual Information” (Facebook, Inc., 30 April 2020), “Video Conference System,
Video Conference Apparatus, and Video Conference Method” (Optoma Corporation, 5 May
2020),” “Speech Recognition and Summarization” (Google LLC, 18 May 2020), “Defining
Content of Interest for Video Conference Endpoints with Multiple Pieces of Content” (CiscoTechnology, Inc., 2 July 2020), and “Sales Management and Video Chat System and Method for
a Salesperson Mobile Device and a Remote Visitor Web Browser” (Dealer Inside, Inc., 7 July2020).
Before turning to our main results, we note there are long and variable lags from thefiling of new patent applications until publication by the USPTO.5 That means our analysis
sample misses a fraction of recent patent filings, and that fraction becomes larger near the end ofour sample. Figure 1 shows the distribution of these lags for all published patent applications that

5 Once the USPTO regards a patent application filing as complete, which can itself be a lengthy

process, the application is assigned for examination. The examination process can also belengthy. The publication of approved patent applications takes about fourteen weeks. The
USPTO has various programs and initiatives to assist in the patent application process, some ofwhich involve additional fees for an expedited process. For more information, see
https://www.uspto.gov/web/offices/pac/mpep/s1120.html, https://www.uspto.gov/patentsgetting-started/patent-process-overview#step6, andhttps://www.uspto.gov/patent/initiatives/uspto-patent-application-initiatives-timeline.
3were first filed from 1 January 2010 to 24 December 2018. The mean lag from filing topublication is 12.9 months for all patent applications and 11.5 months for those that support
WFH technologies. The similarity of the lag structures suggests that the reported percentage offilings accounted for by patent applications that support WFH technologies is unlikely to bemuch distorted by publication lags, even near the end of our sample.6[Figure 1 here]
Figure 2 reports the percentage of newly filed patent applications that support WFH
technologies at a monthly frequency from January 2010 through September 2020. We compute
this percentage as 100 times the ratio of (a) patent application filings in the month that support
WFH technologies to (b) all patent application filings in the month. Interestingly, the WFH shareof new patent applications rises from 0.53 percent in January 2020 to 0.73 percent in February,
before the World Health Organization declared the novel coronavirus outbreak a global
pandemic (Muccari et al., 2020). China reported the first death from COVID-19 in early January
and imposed a lockdown in Wuhan on 23 January. By the end of January, the virus had spread tomany other countries, including the United States. Figure 2 suggests that these developments had
already – by February – triggered the beginnings of a shift in new patent applications toward
technologies that support WFH.
[Figure 2 here]
By March, COVID-19 cases and deaths had exploded in many localities and countries
around the world. Government-mandated lockdowns and voluntary social distancing responses
led to an extraordinary collapse in economic activity. By April and May, half of paid work in the6 We are working on methods to adjust for the variable lags between the filing and publication ofnew patent applications, so that we can estimate recent flow levels as well as shares.
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United States was performed by persons working from home. As Figure 2 shows, the WFH
percentage of new patent applications continued to rise after February. In September 2020, theWFH share of new patent applications reaches 1.16 percent, more than double its January valueand greatly surpassing any month before the pandemic struck. Thus, we find clear evidence thatCOVID-19 has shifted the direction of innovation toward technologies that support WFH.
Other evidence also points to strong commercial incentives to acquire existing WFH
technologies in the wake of the COVID-19 pandemic. For example, Verizon announced on 16April 2020 that it would acquire BlueJeans, a video conferencing firm, for about $500 million(Krause, 2020). Zoom announced on 7 May that it would acquire Keybase, an identity
management firm (O’Flaherty, 2020). Adobe announced on 9 November that it would acquire
Workfront, a leading work management platform for marketers, for $1.5 billion (Bloomberg,2020). And Salesforce announced on 1 December that it had agreed to acquire Slack, aworkplace software company, for $27.7 billion (Griffith and Hirsh, 2020).
It will be interesting to track the flow of new WFH patent applications in the coming
months and years. One possibility is that the recent surge mainly reflects a pipeline acceleration
effect, whereby firms with nearly-completed WFH innovations rush to patent them in response tothe pandemic-induced shift to remote work. In that case, the WFH share might return to its prepandemic baseline in 2021 – or even temporarily fall below its baseline. A second view is thatFigure 2 shows the beginnings of a persistent rise in the flow of new patents that advance WFHtechnologies. The ongoing upward trajectory in the WFH share since the pandemic struck favors
this second view.
Under the second view, the directional shift in innovation will drive continuing
improvements in WFH technologies and the tools and platforms that support WFH activity even5

after the COVID-19 pandemic comes under control. By improving the quality and productivityof remote work activity, a more rapid advance of WFH technologies will reinforce the shift toworking from home even after the pandemic ends.
Barrero, Bloom and Davis (2020) provide evidence of several other mechanisms that will
drive a persistent shift to working from home in the wake of the COVID-19 pandemic. Theseother mechanisms include better-than-expected experiences in working from home since thepandemic struck, investments in physical and human capital that enable and support working
from home, a greatly diminished stigma associated with working from home, and an expressed
desire by many people to avoid public transport and crowded facilities even after the pandemic
ends due to lingering fears of infection risk.

References
Acemoglu, Daron, 1998. “Why Do New Technologies Complement Skills? Directed Technical
Change and Wage Inequality,” Quarterly Journal of Economics, 113, no. 4, 1055-1089.
Barrero, Jose Maria, Nick Bloom, and Steven J. Davis, forthcoming. “COVID-19 Is Also aReallocation Shock.” Brookings Papers on Economic Activity.
Barrero, Jose Maria, Nick Bloom, and Steven J. Davis, 2020. “Why Working from Home WillStick.” Working Paper, December 2020.
Barrero, Jose Maria, Nick Bloom, and Steven J. Davis, 2021. “COVID-19 Is a Persistent
Reallocation Shock.” Paper presented at the American Economic Association meetings.
Bick, Alexander, Adam Blandin and Karel Mertens, 2020. “Work from Home after the COVID19 Outbreak,” Federal Reserve Bank of Dallas Working Paper 2017, June.
Bloomberg, 2020. “Adobe to Acquire Workfront,” 9 November.

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Brynjolfsson, Eric, John J. Horton, Adam Ozimek, Daniel Rock, Garima Sharma and Hong-YiTuYe, 2020. “COVID-19 and Remote Work: An Early Look at U.S. Data,” NBER Working
Paper 27344.
Griffith, Erin and Lauren Hirsh, 2020. “Salesforce to Acquire Slack for $27.7 Billion,” New YorkTimes, 1 December.
Krouse, Sarah, 2020. “Verizon Buys Zoom Conferencing Rival BlueJeans,” Wall Street Journal,
16 April.
Muccari R., Chow D. and Murphy J., 2020. “Coronavirus timeline: Tracking the critical momentsof COVID-19,” NBC News, updated 8 July.
O’Flaherty, Kate, 2020. “Zoom Buys Keybase in Bold New Security Move,” Forbes, 7 May.
Ozimek, Adam, 2020. “The Future of Remote Work,” SSRN Working Paper.
Pagano, Marco, Christian Wagner and Joseph Zechner, 2020. “Disaster Resilience and AssetPrices,” COVID Economics: Vetted and Real-Time Papers, Issue 21, 22 May.
Papanikolaou, Dimitris and Lawrence D.W. Schmidt, 2020. “Working Remotely and the SupplySide Impact of COVID-19,” NBER Working Paper No. 27330.

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Figure 1. Lags in the Filing of Patent Applications to their Publication by the USPTO

Source: Authors’ analysis of XML files of published patent applications that were filed with theUnited States Patent and Trademark Office from 1 January 2010 through 24 December 2018.
Figure 2. Percent of New Patent Applications that Support Work-from-Home Technologies,
January 2010 to September 2020
Percent
1.21.1February
2020

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0.7
0.6
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Jan12
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Jan15
Ju
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Ja
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Ju
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Jan18
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Jan19
Ju
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Jan20
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00.3

Source: Authors’ analysis of XML files of patent applications published by the USPTO from 7January 2010 through 24 December 2020, covering filings through 11 September 2020.
Note: The chart reports the percentage of patent application filings through 11 September 2020
that support WFH technologies. We calculate this percentage using our automated classificationof invention descriptions in patent applications published through 24 December 2020.

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