An easier way to do this is just to break up these companies directly. Monopolies or duoplies or x-opolies should be broken up, just like AT&T and Standard Oil.

Having these monopolies (defining loosely - whether one company or a 2 or 3 or 4) is the main deficiency of capitalism.

Unfortunately, breaking up monopolies or increases taxes is exceedingly difficult to do as large companies and their lobbying congress prevents it in most cases.