"There's a cheat-code in US antitrust law, one that's been increasingly used since the Reagan administration, when the "consumer welfare" theory ("monopolies are fine, so long as the lower prices") shoved aside the long-established idea that antitrust law existed to prevent monopolies from forming at all."
Antitrust law governs anti-competitive conduct, not the formation of monopolies (cf. "trusts", as they were known at the time the Sherman Act was passed). There is is nothing illegal about forming a monopoly. The question is whether the defendant used their monopoly position to engage in anti-competitive practices.
> Antitrust law governs anti-competitive conduct, not the formation of monopolies (cf. "trusts", as they were known at the time the Sherman Act was passed). There is is nothing illegal about forming a monopoly. The question is whether the defendant used their monopoly position to engage in anti-competitive practices.
It's more complicated than that; "Innocent monopolies" (i.e. those that occur and are maintained without any anticompetitive practices) are allowed, but the list of things you can't do to form or maintain them (particularly after the Clayton act) makes it rather hard. For example, Mergers and Acquisitions that are likely to "substantially reduce market competition" are not allowed, so forming a monopoly by buying out your competitors would seem to violate the intent of the law.
I am by no means an expert on US anti-trust law but the first sentence of the Wikipedia page[0] on the topic says
> In the United States, antitrust law is a collection of mostly federal laws that regulate the conduct and organization of businesses to promote competition and prevent unjustified monopolies.
The first paragraph finishes with
> Section 2 of the Sherman Act prohibits monopolization.
And in fact the word "monopoly" (or its derivatives) appear 76 times, so it seems to be at least an important component of the law.
"Holding a dominant position or a monopoly in a market is often not illegal in itself; however, certain categories of behavior can be considered abusive and therefore incur legal sanctions when business is dominant."
Antitrust law governs anti-competitive conduct, not the formation of monopolies (cf. "trusts", as they were known at the time the Sherman Act was passed). There is is nothing illegal about forming a monopoly. The question is whether the defendant used their monopoly position to engage in anti-competitive practices.