You're playing with fire. Monopolies that form naturally also perish naturally (and quickly). Consider Rockefeller & Standard Oil. They got 90% of the market

You're playing with fire. Monopolies that form naturally also perish naturally (and quickly). Consider Rockefeller & Standard Oil. They got 90% of the market and bought the trains so as to force their competition to pay 200% more in shipping. But by the time the government antitrust case started, Standard Oil's market share had naturally fallen to ~60%. On the other hand, if you solve the problem with regulation, then the regulated body has a powerful tool for maintaining their monopoly: forcing their regulation onto their startup competitors. For example VOIP got saddled with regulation for local 911 calling and easy government wiretapping. Internet radio has to pay some of the worst rates possible under the agreement content producers made with radio stations -- I think this is largely due to gov involvement in radio.