Big Banks

There are five big banks, four big airlines, one dominant social-media company, one maker of EpiPens. A small set of institutional investors—BlackRock, Fidelity, Vanguard—holds stock in a vast percentage of public companies, so even sectors that look somewhat competitive are less so than they appear. CVS and Walgreens, for instance, have a strikingly similar set of major shareholders. The same is true for Apple and Microsoft. Such business concentration is a leading cause of inequality and wage stagnation.