From the NBER:
Immigrants and Firms' Outcomes: Evidence from France, by Cristina Mitaritonna, Gianluca Orefice, and Giovanni Peri, NBER Working Paper No. 22852 Issued in November 2016: In this paper we analyze the impact of an increase in the local supply of immigrants on firms’ outcomes, allowing for heterogeneous effects across firms according to their initial productivity. Using micro-level data on French manufacturing firms spanning the period 1995-2005, we show that a supply-driven increase in the share of foreign-born workers in a French department (a small geographic area) increased the total factor productivity of firms in that department. Immigrants were prevalently highly educated and this effect is consistent with a positive complementarity and spillover effects from their skills. We also find this effect to be significantly stronger for firms with low initial productivity and small size. The positive productivity effect of immigrants was also associated with faster growth of capital, larger exports and higher wages for natives. Highly skilled natives were pushed towards firms that did not hire too many immigrants spreading positive productivity effects to those firms too. Because of stronger effects on smaller and initially less productive firms, the aggregate effects of immigrants at the department level on average productivity and employment was small.