> ...In US, a company can be a complete monopoly, wiping out all competition, and still not cross the line for anti-trust purposes. That's actually allowed by

> ...In US, a company can be a complete monopoly, wiping out all competition, and still not cross the line for anti-trust purposes. That's actually allowed by the contestable-market framing, at least in some cases. It all depends what you mean by "a complete monopoly" and "wiping out" competition - does it happen via some "natural" cost advantages, or has the company been building up an abusive "moat" around their position. Though even in the former case, economic theory implies that forcing a break-up of the firm that isolates the "naturally dominating" part of its business, and then subjecting that to appropriate regulation and market-openness requirements, can be a highly efficient approach and lead to improved consumer welfare.