Not really. Monopolies are an invitation to competition: Your margin is my opportunity, as it were. They are therefore hard to maintain absent some kind of external force to support it: Regulations (regulatory capture), licensing, explicit grant from the government, intellectual property laws, or some kind of collusion or market manipulation (more leading to oligopolies rather than monopolies).
This is how industrial barons of the early-mid 20th century operated, as an example, with collusion and price fixing type things. Or hospitals and medical facilities today with certificate-of-need laws enforced by the government.
This is how industrial barons of the early-mid 20th century operated, as an example, with collusion and price fixing type things. Or hospitals and medical facilities today with certificate-of-need laws enforced by the government.