It's called partners.
Let alone that some 咨询,投行 offer top pathways to become equity owners - either as top officers of large corp, or as new venture founders, or major private investors.
McK alone has >70 alumni became CEO of F500 companies. At VP level or other cXo level, their number is in the thousands.
Now you can still call them as 打工 . But their ownership of company stocks could worth hundreds of millions, or even in the billions.