[1.2.4c] Oligopoly
Oligopoly
An oligopoly is a market dominated by a small number of large firms. Each holds a significant market share and recognises that its decisions directly affect — and are affected by — its rivals. This mutual interdependence is the defining characteristic of oligopoly and shapes how firms in these markets behave.
Examples: global smartphones (Apple, Samsung); UK grocery (Tesco, Sainsbury's, Asda, Morrisons); global aviation; international oil companies.
Main Features
- Few large firms dominate: a small number of large firms account for most market output and sales — the market is highly concentrated.
- Differentiated products: unlike perfect competition, oligopolists offer products with real or perceived differences built through features, branding and marketing.
- Barriers to entry: high barriers (economies of scale, brand loyalty, capital requirements) protect dominant firms and prevent meaningful new entry.
- Mutual interdependence: each firm's pricing or output decision measurably affects rivals, requiring each to anticipate how rivals will react before acting.
Collusion vs Competition
Oligopolists face a fundamental tension: they have an incentive to cooperate (collude to keep prices high and profits large) but also to compete to gain market share.
Collusion occurs when firms agree — formally or informally — to fix prices, divide markets or restrict output, allowing them collectively to act like a monopolist. A formal agreement is called a cartel (e.g. OPEC). Cartels are illegal in most countries as they harm consumers. Tacit collusion (price leadership) is more common in legal markets — one dominant firm sets a price and rivals follow without any explicit agreement.
Price wars can erupt when one firm cuts price to gain share and rivals retaliate. They damage all participants' profitability since every firm must match cuts. Because rivals always respond, no firm gains a lasting advantage — but all lose margin. This is why oligopolists often maintain stable prices (price stickiness) even when costs change.
Non-price competition is the preferred strategy — it builds market share without triggering a price war. Methods include advertising and branding, product quality and features, customer service and loyalty programmes, and packaging and convenience. Each firm differentiates on dimensions where rivals cannot easily retaliate with an immediate price cut.
Advantages and Disadvantages of Oligopoly
| Dimension | Advantage | Disadvantage |
|---|---|---|
| Choice | Multiple large firms offer differentiated products, giving consumers options across a range. | Fewer firms than in competitive markets limits variety compared to perfect competition. |
| Quality | Non-price rivalry encourages quality investment as firms compete on dimensions beyond price. | If firms collude, quality improvements may be neglected once competitive pressure eases. |
| Innovation | Large profits and R&D budgets allow significant investment. Rivalry between oligopolists (e.g. smartphone features) drives continual innovation. | Collusion reduces competitive pressure to innovate — comfortable profits may be extracted without product improvement. |
| Price | Price wars can temporarily deliver significant price reductions to consumers. | Cartels and tacit collusion fix prices above the competitive level. Price stability may mask above-normal profit extraction. |
Key Takeaways
- An oligopoly is a market dominated by a few large firms with significant barriers to entry.
- Mutual interdependence: each firm's decisions directly affect rivals, shaping behaviour.
- Collusion (formal cartels or tacit price leadership) allows firms to act collectively like a monopolist — illegal but common tacitly.
- Price wars harm all participants; oligopolists often prefer non-price competition to avoid them.
- Oligopoly offers some benefits (choice, innovation, quality rivalry) but risks collusive exploitation.