This paper compares the extent of common ownership in the US and the EU stock markets, with a particular focus on differences in the applicable ownership transparency requirements. Most empirical research on common ownership to date has focused on US issuers, largely relying on ownership data...

We construct a novel data set to show that, between 2003-2020, up to one-fifth of America's largest firms had a non-financial blockholder or insider as their largest shareholder. Blockholders and insiders tend to be less diversified than institutional investors. Measures of "universal" and...