The Wall Street Journal has a long list.[1]
It works for Putin.
Just a few weeks ago, an American friend was making the comparison between the number of billion $ companies in the EU vs the US. I was trying to tell them that it isn't necessarily a bad thing to have less of that - I rather have 1,000 million $ companies than a billion $ one. The concentration of financial power seems so unhealthy, and it looks like it's crippling the whole American system.
Business in the US is underappreciated in so many ways.
So the concentration of economic power has made the number of oligarchs he needs to capture quite manageable.
Except in the real world the bn $ company will dump and outright buy the puny million dollar companies. It will do everything in its power, which is a lot, legally and illegally, to destroy the competition. That's just the way capitalism works.