Migration and Innovation Diffusion

Francesco Lissoni
Thursday, December 15, 2016

How does the migration of highly skilled people affect the number of patents and the diffusion of innovations? If highly skilled migrants arrive, does the rate of patenting rise in the destination country, the origin country, or both?


Francesco Lissoni of the University of Bordeaux on December 15, 2016 explained that some argue that the “main channel for the diffusion of innovations has been the migration of people.” Patents originated in the 1500s, when European leaders gave migrant craftsmen temporary monopoly on their craft in exchange for training local apprentices. Religious minorities driven out of one country were another source of innovation in destination countries, such as Protestant Huguenots driven out of France after 1685 who settled in the UK and Prussia.

How do we measure the effects of highly skilled migrants today? Many Russian scientists left after the USSR collapsed in the early 1990s, and some studies found that the presence of Russian mathematicians in the US displaced US mathematicians, who shifted away from math subfields in which Russian newcomers predominated. Once in another country, immigrants from the same country often collaborate, which can raise publication rates, since co-authorship of scientific papers often increases with co-ethnicity.

About 20 percent of patents filed in the US, and 10 percent of those filed in Europe, include foreigners as inventors; the US granted about 326,000 patents in 2015. Multinationals have operations in several countries and usually have diverse workforces. Some data suggest that collaboration between workers from the same country leads to more patents filed, a rejection of the theory that diverse work teams are more innovative. Across US states, subsidiaries of multinationals from a particular country are associated with more people born in that country, as with Germans in South Carolina.

Do highly skilled migrants benefit their countries of origin if they return? Taiwanese and Chinese who studied and worked in the US and later returned are often credited with launching successful enterprises at home and facilitating technology and business operation transfers from the US to Taiwan and China. A study of Fulbright scholars who graduated from US universities and were required to return home found that they generated more papers with US-based co-authors than their compatriots who stayed home, keeping origin-country research linked to US research.

Diasporas abroad may increase trade by reducing trade costs and could affect patent rates. Middle-income countries such as China and India have many of their PhDs who file for patents abroad, and this disapora tends to cite other foreign rather than country-of-origin patents.

Lissoni cautioned that there are many data issues with measuring the interactions of skilled migration, patents and innovation. Many studies are based on looking at names on patents and publications to determine which people are co-ethnics. Patents are often filed by multiple people, and sometimes list company rather personal addresses, making it hard to know where inventors live and work. Finally, most patents are in only a few fields, including chemistry, pharmacology and electrical engineering.