In the US, the closest that exists is mutual fund ownership (form 13F) and company insider ownership (forms 3, 4, & 5) filings: https://www.sec.gov/fast-answer

In the US, the closest that exists is mutual fund ownership (form 13F) and company insider ownership (forms 3, 4, & 5) filings: https://www.sec.gov/fast-answers/answers-form13fhtm.html https://www.sec.gov/fast-answers/answers-form13fhtm.html https://www.sec.gov/cgi-bin/browse-edgar?company=&CIK=&type=4&owner=only&count=40&action=getcurrent https://www.sec.gov/cgi-bin/browse-edgar?company=&CIK=&type=... These forms are only submitted about public companies. You can see the data on sites like Yahoo Finance.