専売

A monopoly is a market structure with a single seller offering a unique product without close substitutes. The monopolist operates without competition and acts as the price maker, controlling both supply and pricing. For example, Microsoft dominated personal computer operating systems in the 1990s with Windows, giving the company complete control over pricing decisions.

Barriers to entry include high startup costs, exclusive control over essential raw materials, and legal restrictions. Google exemplifies this through its search engine dominance, created by its user base, advanced algorithms, and substantial data collection capabilities. Understanding reasons for the existence of monopoly helps explain how these barriers prevent competitors from entering the market.

Network effects occur when a product's value increases as more people use it, creating natural monopolies. Social media platforms exemplify this, where increased user bases make the platform more valuable. This self-reinforcing mechanism makes it difficult for competitors to challenge established monopolies since users benefit from the existing network.

Yes, monopolies can benefit society in specific contexts. Natural monopolies like public utilities—water and electricity suppliers—are sometimes granted monopoly status to preserve efficient service delivery. Additionally, some monopolies foster technological innovation or provide essential services in markets where competition is economically unfeasible.

A monopolist is a price maker who can influence market price by adjusting output, unlike firms in competitive markets. This pricing power stems from being the sole provider of a unique product with no close substitutes. The monopolist can maintain higher prices and restrict output without losing customers to competitors.

Monopolies can lead to higher prices, reduced innovation, and limited consumer options due to the absence of competition. Without competitive pressure, monopolists have less incentive to improve products or reduce costs. Consumers face restricted choices and may pay premium prices for products they cannot obtain elsewhere.

Exclusive control over essential raw materials or key technologies creates significant barriers preventing competitors from entering the market. De Beers historically maintained diamond industry dominance through controlling most production and distribution worldwide. This resource monopoly allows firms to sustain their market position and pricing power indefinitely.