An oligopoly has a few large sellers, strong interdependence, high entry barriers, homogeneous or differentiated products, price rigidity (kinked demand curve), non-price competition, heavy advertising, price leadership, risk of collusion, occasional price wars, consolidation through mergers, and decision-making best explained by game theory.
India’s mobile phone market is a textbook oligopoly. After years of price wars and exits, Jio, Airtel and Vodafone Idea serve almost all private subscribers, with state-owned BSNL far behind. When one raised tariffs in mid-2024, the others followed within days. That reaction, where each firm watches and responds to the others, is the defining feature of oligopoly.
An oligopoly is a market dominated by a few large sellers. Other Indian examples include cement, aviation (IndiGo and the Air India group carry most domestic passengers) and passenger cars. Here are its main characteristics. Compare with other market structures.
12 Characteristics of an Oligopoly
1. Few Large Sellers
A small number of firms control most of the market. Economists often measure this with the concentration ratio, such as the combined share of the top four firms.
2. Interdependence
Each firm’s decisions on price, output or advertising affect its rivals, so every move depends on how others are expected to react.
3. High Barriers to Entry
Huge capital needs, spectrum licences, patents, economies of scale or brand loyalty keep newcomers out.
4. Homogeneous or Differentiated Products
Pure oligopolies sell near-identical products (cement, steel); differentiated oligopolies sell branded products (cars, smartphones).
5. Price Rigidity
Prices tend to stay stable. Paul Sweezy’s kinked demand curve (1939) explains why: rivals match price cuts but ignore price rises, so no firm gains by changing price alone.
6. Non-Price Competition
Firms compete on advertising, features, service and loyalty schemes rather than price.
7. Heavy Advertising
Brand building is central, which is why telecom, car and soft-drink companies are among the biggest advertisers.
8. Price Leadership
One firm, often the largest, sets prices and others follow.
9. Risk of Collusion
Firms may coordinate prices or output, which is illegal. The Competition Commission of India fined cement makers over ₹6,000 crore in 2016 for cartelisation.
10. Price Wars
When cooperation breaks down, firms cut prices aggressively. Jio’s 2016 launch with free data triggered a price war that pushed several telecom operators out.
11. Mergers and Acquisitions
Firms consolidate to gain scale, as Vodafone and Idea did in 2018.
12. Game Theory Applies
Strategic decisions resemble games such as the prisoner’s dilemma, where both firms might do better cooperating but each has an incentive to cheat.
Oligopoly vs Other Market Structures
| Feature | Perfect competition | Monopolistic competition | Oligopoly | Monopoly |
|---|---|---|---|---|
| Number of sellers | Very many | Many | Few | One |
| Product | Identical | Differentiated | Identical or differentiated | Unique |
| Entry | Free | Fairly easy | Difficult | Blocked |
| Price control | None | Some | Considerable, interdependent | High |
| Example | Farm produce | Restaurants | Telecom, cement | Indian Railways (passenger rail) |
Related: features of monopoly and characteristics of monopolistic competition.
