That's why he talks about barriers to entry and market power because using those things to prevent competition is illegal. Sherman Act is actually a criminal st

That's why he talks about barriers to entry and market power because using those things to prevent competition is illegal. Sherman Act is actually a criminal statue that can put executives behind bars. There's also the Clayton Act and Robinson Patman act that ban forms of monopolization and price discrimination. It's up to the courts to determine what's reasonable. > Section 2 of the Sherman Act makes it unlawful for a company to "monopolize, or attempt to monopolize," trade or commerce. As that law has been interpreted, it is not illegal for a company to have a monopoly, to charge "high prices," or to try to achieve a monopoly position by what might be viewed by some as particularly aggressive methods. The law is violated only if the company tries to maintain or acquire a monopoly through unreasonable methods. For the courts, a key factor in determining what is unreasonable is whether the practice has a legitimate business justification. https://www.ftc.gov/advice-guidance/competition-guidance/guide-antitrust-laws/single-firm-conduct https://www.ftc.gov/advice-guidance/competition-guidance/gui...