This is shown by a study of the situation in 14 high-income countries such as Germany, the USA, Japan, Israel and South Korea.

Gergely Hajdu (Assistant Professor at the Department of Economics): "The study shows that earnings polarization between workplaces is growing in most places, and this reflects more skill homogenous firms, produced by new firms being more specialized and older larger firms outsourcing many tasks."

Gergely was interviewed in Ö1 Mittagsjournal on April 30th 2020. You can read more about it on the ORF Website (in German): Ungleichheit der Einkommen steigt (ORF, May 1st, 2020)

Link to the study: https://www.pnas.org/content/117/17/9277

Abstract:

It is well documented that earnings inequalities have risen in many high-income countries. Less clear are the linkages between rising income inequality and workplace dynamics, how within- and between-workplace inequality varies across countries, and to what extent these inequalities are moderated by national labor market institutions. In order to describe changes in the initial between- and within-firm market income distribution we analyze administrative records for 2,000,000,000+ job years nested within 50,000,000+ workplace years for 14 high-income countries in North America, Scandinavia, Continental and Eastern Europe, the Middle East, and East Asia. We find that countries vary a great deal in their levels and trends in earnings inequality but that the between-workplace share of wage inequality is growing in almost all countries examined and is in no country declining. We also find that earnings inequalities and the share of between-workplace inequalities are lower and grew less strongly in countries with stronger institutional employment protections and rose faster when these labor market protections weakened. Our findings suggest that firm-level restructuring and increasing wage inequalities between workplaces are more central contributors to rising income inequality than previously recognized.