Oligopoly can be defined as a market condition or structure in which a relatively small number of large firms account for a substantial share of market activity. Ontologically, oligopoly is a form of imperfect competition (Gregova, 2009). Unlike perfect competition, where individual firms are essentially price takers, firms in an oligopolistic market are strategically interdependent: the pricing, investment, output, advertising and capacity decisions of one firm affect the decisions and profitability of its rivals.
This makes oligopoly particularly important for understanding modern Indian industry.
The Indian economy contains several sectors in which a handful of large companies exercise considerable market influence. Telecom, aviation, paints, steel, cement, passenger vehicles and tyres are prominent examples, although the degree of concentration differs considerably across them. Recent analysis of Indian industries shows that aviation, telecom, paints, steel and two-wheelers fall into the category of highly concentrated markets under the commonly used Herfindahl-Hirschman Index (HHI) threshold, while cement, tyres and passenger vehicles are moderately concentrated.
The important point, however, is that market concentration is not synonymous with oligopoly. A high HHI indicates concentration, but the existence of an oligopoly also depends on the number of significant competitors, barriers to entry, product substitutability and, critically, the strategic interaction between firms.
This is where game theory becomes particularly useful.
Oligopoly and the logic of game theory
John Nash’s contribution to game theory provides an important framework for understanding oligopolistic competition. Nash equilibrium describes a situation in which each player chooses the best strategy given the strategies chosen by the other players. In an oligopoly, firms cannot make decisions in isolation because every major strategic decision may provoke a response from competitors.
Nash’s observation that “interdependence is the distinguishing feature of games of strategy” captures the central problem facing oligopolists (Piraino Jr., 2004).
Consider two large firms contemplating a price reduction. Each firm would prefer to maintain a high price if the other does so. Yet each has an incentive to cut prices if it believes the rival will maintain its price. If both firms cut prices, however, both may end up worse off.
The same strategic interaction occurs with:
- production capacity;
- discounts;
- advertising;
- product launches;
- dealer incentives;
- network investment;
- acquisitions;
- geographic expansion;
- technological investment; and
- pricing.
This explains why oligopolistic markets can sometimes produce relatively stable prices without an explicit agreement among competitors. Firms may learn from one another, anticipate retaliation and avoid strategies that could trigger a destructive price war.
That is tacit coordination, and it should not automatically be confused with illegal cartel behaviour.
India’s contemporary industrial landscape provides several striking examples.
1. Telecom: India’s clearest modern oligopoly
India’s telecom industry is perhaps the strongest contemporary example of oligopolistic competition.
The sector underwent extraordinary consolidation following the entry of Reliance Jio, forcing several older operators either to merge, exit or dramatically alter their strategies. The market that once contained numerous significant mobile operators has effectively become dominated by a small group of national players.
The latest government data illustrate the concentration. At the end of May 2026, Reliance Jio had about 515.14 million wireless subscribers, Bharti Airtel about 365.13 million and Vodafone Idea about 129.21 million, while BSNL had about 23.02 million. The top five wireless broadband providers accounted for virtually the entire market.
The strategic interaction between Jio, Airtel and Vodafone Idea demonstrates the essence of oligopoly.
When Jio entered the market with extremely aggressive pricing and large data allowances, competitors had to respond. Airtel invested heavily in 4G and subsequently 5G, Vodafone Idea sought to preserve its subscriber base and network competitiveness, while BSNL pursued a different strategy through its government-supported network expansion.
The important economic feature is that each firm’s strategy is conditional on what it expects its rivals to do.
Airtel cannot determine its tariff strategy without considering Jio. Jio cannot determine its investment programme without considering Airtel. Vodafone Idea’s pricing and capital expenditure decisions are similarly shaped by the strategies of the two market leaders.
This is textbook strategic interdependence.
Telecom also illustrates an important barrier to entry. A new nationwide operator requires enormous capital investment in spectrum, networks, towers, fibre, technology, distribution and customer acquisition. Consequently, the threat of potential entry is considerably weaker than in an industry where a new competitor can enter at relatively low cost.
The game-theory lesson
Telecom demonstrates that oligopoly does not require firms to explicitly collude. Repeated interaction can itself create strategic discipline.
If three major firms compete repeatedly over prices and customers, each understands that an aggressive move today can trigger a response tomorrow. The resulting equilibrium may therefore differ substantially from the outcome of one-shot competition.
2. Aviation: concentration at extraordinary levels
India’s airline industry has emerged as another powerful example of oligopolistic market structure.
The sector’s concentration has become especially visible following the consolidation of the Tata Group’s airline businesses and the extraordinary expansion of IndiGo.
In June 2026, IndiGo held approximately 66.3% of India’s domestic passenger market, while the Air India Group accounted for about 23.9%. Akasa Air was a distant third with 6.4%, while SpiceJet had fallen below 2%.
The concentration is therefore not simply a theoretical observation. Two airline groups account for the overwhelming majority of domestic passenger traffic.
The strategic consequences are significant.
An airline’s pricing decision depends upon:
- the routes operated by rivals;
- available aircraft capacity;
- airport slots;
- fuel prices;
- passenger demand;
- competitor fares;
- fleet expansion;
- load factors; and
- expected future capacity.
For example, if IndiGo significantly increases capacity on a particular route, Air India must decide whether to match the capacity, reduce prices, differentiate its service or redeploy aircraft elsewhere.
This is a strategic game.
The high fixed costs of aviation further intensify the problem. Aircraft are expensive assets that airlines want to keep productive. An empty seat represents perishable inventory: once a flight departs, that capacity cannot be sold later.
Consequently, airlines continuously optimise the interaction between price and capacity.
Why aviation matters for consumers
An oligopoly does not necessarily mean that consumers are always worse off. Large firms can exploit economies of scale, operate extensive networks and invest in technology and infrastructure.
But high concentration can increase the potential for market power.
This is why India’s aviation market has attracted regulatory attention. A 2026 analysis placed the industry’s HHI at approximately 4,400 based on FY23 revenue, while IndiGo and the Air India Group together accounted for about 91% of domestic passenger traffic in July 2026.
The economic question is therefore not merely whether airlines are large, but whether competition between them remains sufficiently strong to constrain market power.
3. Paints: an oligopoly under attack from a new entrant
India’s decorative paints industry offers one of the most interesting examples of how an established oligopoly can be disrupted by a deep-pocketed new entrant.
For decades, Asian Paints, Berger Paints and Kansai Nerolac occupied dominant positions in the market. The industry possessed significant barriers to entry, including distribution networks, dealer relationships, tinting infrastructure, brand recognition and relationships with painters and contractors.
The structure was therefore conducive to sustained oligopolistic competition.
However, the arrival of Birla Opus, backed by the Aditya Birla Group, has changed the competitive dynamics.
Reuters reported in 2025 that Asian Paints’ market share had fallen from approximately 59% to 52%, while Birla Opus had captured about 6.8% within roughly a year of its launch.
The competitive response demonstrates game theory in action.
A new entrant does not merely add another supplier. It changes the strategic game for every incumbent.
Existing firms have to decide whether to:
- reduce prices;
- increase dealer incentives;
- invest in advertising;
- introduce new products;
- expand distribution;
- strengthen relationships with painters; or
- differentiate through premiumisation and technology.
Birla Opus has consequently transformed what was historically a relatively stable competitive structure into a much more aggressive contest.
Grasim reported that its paints business strengthened its position to number three in FY26, supported by more than 50,000 dealers and 450,000 active contractors and painters.
This is important because distribution itself is a strategic asset.
The paint industry illustrates that oligopoly is not simply about having a few firms. It is about the strategic assets that make those firms difficult to displace.
4. Steel: scale, consolidation and strategic capacity
Steel is another important example of concentration in Indian industry.
The sector has undergone considerable consolidation, with large producers gaining scale through organic expansion as well as acquisitions. Recent analysis found the combined revenue share of India’s two largest steel companies had increased from approximately 44.5% in FY15 to 57.6% in FY24.
Steel has several structural characteristics that favour large-scale firms.
Production requires:
- substantial capital;
- large plants;
- access to raw materials;
- energy;
- logistics;
- technology;
- distribution networks; and
- significant working capital.
These requirements create barriers to entry.
The strategic game in steel is therefore often less about short-term retail pricing and more about capacity expansion and long-term market positioning.
If one major producer announces a large increase in capacity, competitors must evaluate whether the move threatens their market share. They may respond with their own capacity investments, acquisitions, exports or product differentiation.
This creates a repeated strategic game in which firms must anticipate one another’s investment decisions years into the future.
The result can be a market in which the largest companies possess substantial influence over industry capacity and competitive conditions.
5. Cement: concentrated, but not a simple textbook oligopoly
Cement is particularly interesting because it demonstrates why analysts should be careful when labelling an industry an oligopoly.
India has many cement producers, and the industry remains more fragmented than telecom or aviation. Nevertheless, the largest producers account for a substantial proportion of capacity.
An industry analysis for FY24 estimated UltraTech’s capacity share at 23.6%, while the Adani Group’s cement businesses accounted for about 13.2%. Shree Cement and Dalmia Bharat followed with approximately 8.4% and 7.8%, respectively. The top ten producers together accounted for about 74.4% of installed capacity.
The market has subsequently become even more strategically important because of consolidation.
In 2026, the Ambuja-ACC group, part of the Adani Group, had reached approximately 109 million tonnes of annual cement capacity and was targeting 119 million tonnes by FY27. The group held an estimated 16.6% market share as of September 2025.
Cement therefore exhibits many characteristics associated with oligopoly:
- high fixed investment;
- economies of scale;
- substantial transportation costs;
- regional concentration;
- capacity constraints;
- acquisitions;
- large incumbents; and
- strategic interdependence.
But there is an important qualification.
Cement markets are strongly regional. A company may be a powerful national producer while facing considerably more competition in a particular state or region.
Therefore, the relevant market matters.
Calling cement an Indian oligopoly without considering geography can oversimplify the structure.
6. Passenger vehicles: a concentrated but increasingly competitive market
India’s passenger vehicle industry provides another useful case.
The sector contains several significant manufacturers, but the largest firms command substantial market shares.
In 2025, Maruti Suzuki remained the market leader with approximately 39.9% of sales. Mahindra accounted for 13.3%, Tata Motors 12.7% and Hyundai 12.5%. Toyota, Kia and other manufacturers occupied smaller positions.
The four largest manufacturers therefore accounted for roughly three-quarters of the market.
Yet this should not automatically be described as a four-firm cartel or even a rigid oligopoly.
Competition is intense because firms compete across multiple dimensions:
- price;
- fuel efficiency;
- SUVs;
- electric vehicles;
- safety;
- technology;
- financing;
- after-sales service; and
- brand image.
The arrival and expansion of Mahindra, Tata Motors and other manufacturers has also altered the strategic balance.
The electric-vehicle transition adds another layer to the game.
A manufacturer must decide how quickly to invest in EV technology without knowing exactly how quickly consumer demand will shift. If one company moves too slowly, it risks losing technological leadership. If it invests too aggressively, it risks tying up capital in a market that develops more slowly than expected.
This is a classic strategic investment problem under uncertainty.
7. Tyres: another example of concentrated competition
India’s tyre industry also displays important oligopolistic characteristics.
The industry requires substantial manufacturing capacity, technology, distribution infrastructure and relationships with automobile manufacturers. Major players compete for both original-equipment manufacturers and replacement-market consumers.
Recent sectoral analysis placed India’s tyre industry in the moderately concentrated category, with an HHI of around 2,001 in FY24.
The competitive structure is therefore different from aviation or telecom but still demonstrates strategic interdependence.
A major tyre manufacturer changing prices can influence the behaviour of competitors. Similarly, an OEM contract can materially affect production economics and market positioning.
The replacement market also introduces brand loyalty and distribution advantages, making it difficult for small entrants to immediately challenge established manufacturers.
What makes India’s oligopolies different?
India’s oligopolistic sectors share several structural characteristics.
1. High barriers to entry
Telecom requires spectrum and network investment. Aviation requires aircraft, airport slots and regulatory approvals. Cement and steel require enormous capital investment. Paints require distribution and dealer networks.
High entry barriers reduce the threat posed by potential competitors.
2. Economies of scale
Large firms can spread fixed costs over enormous volumes.
This creates a feedback loop:
scale → lower unit costs → competitive advantage → greater market share → more scale
The process can make established firms increasingly difficult to challenge.
3. Strategic interdependence
The defining characteristic of oligopoly is that firms must anticipate rivals.
Airtel watches Jio.
Air India watches IndiGo.
Asian Paints watches Birla Opus.
UltraTech watches Ambuja and other major cement producers.
Maruti watches Mahindra, Tata and Hyundai.
The decision of one company becomes information for all the others.
4. Repeated interaction
These firms rarely interact only once.
They compete repeatedly every day, every quarter and every year.
Repeated interaction can produce more sophisticated strategies than one-time competition. Firms can reward aggressive competitive behaviour, respond to rivals’ moves and learn from previous market outcomes.
This helps explain why oligopolistic markets sometimes exhibit relatively stable pricing even when firms have strong incentives to compete.
5. Non-price competition
Oligopoly does not necessarily produce constant price wars.
Firms may instead compete through:
- advertising;
- technology;
- product differentiation;
- customer service;
- loyalty programmes;
- dealer incentives;
- network quality;
- brand reputation; and
- innovation.
This is especially visible in automobiles and paints.
Oligopoly does not necessarily mean collusion
One of the most important distinctions in analysing Indian oligopolies is between strategic interdependence and illegal collusion.
Game theory demonstrates that firms can reach outcomes that resemble coordination without necessarily entering into an explicit agreement. Suppose two firms repeatedly compete in the same market. Each understands that an aggressive price cut today may provoke a matching price cut tomorrow. Both may therefore decide that maintaining relatively stable prices is strategically preferable. That does not by itself establish an illegal cartel.
Explicit agreements to fix prices, divide markets or restrict competition are a different matter and may violate competition law. The distinction matters because oligopoly is fundamentally a market structure, whereas collusion is a behavioural and legal issue. A concentrated market may be fiercely competitive. Conversely, a market with only a few firms may create conditions in which coordination becomes easier.
India’s oligopoly story is changing
The most interesting feature of India’s current industrial landscape is that oligopoly is not static.
Three forces are continuously changing the structure of markets.
Consolidation
Mergers and acquisitions are increasing the scale of leading firms. Cement is a particularly visible example.
New entrants with deep capital
Birla Opus demonstrates how a financially powerful entrant can challenge an established industry structure.
Technology
Digital platforms, artificial intelligence, electric vehicles, 5G and automation can reduce some traditional barriers while creating entirely new ones.
The result is a paradox.
Technology can make markets more contestable by lowering some entry costs, but it can simultaneously increase concentration by rewarding firms that possess enormous amounts of capital, data, infrastructure or network effects.
Conclusion: India’s oligopolies are strategic games, not simply markets with few firms
India’s major concentrated industries provide a real-world demonstration of the central insight of game theory: firms do not make strategic decisions independently when their fortunes are intertwined with the decisions of a small number of powerful rivals.
Telecom is dominated by a few large network operators. Aviation has become extraordinarily concentrated around IndiGo and the Air India Group. Paints are experiencing a new competitive battle after the arrival of Birla Opus. Steel is increasingly shaped by large integrated producers. Cement is consolidating around major groups, while automobiles and tyres remain concentrated but comparatively more competitive.
The degree of oligopoly varies considerably between these industries. Aviation and telecom currently display particularly strong concentration, while cement, passenger vehicles and tyres occupy a more nuanced position.
The central economic lesson is therefore not simply that “a few firms dominate.”
It is that the behaviour of each firm is conditional on the expected behaviour of its rivals.
That is the essence of oligopolistic competition.
Nash equilibrium provides a useful conceptual lens for understanding this interdependence. Firms seek strategies that maximise their own returns, but their optimal strategy depends on what competitors are expected to do. The resulting equilibrium can involve aggressive competition, product differentiation, investment races, relatively stable prices or, where legally impermissible coordination occurs, collusion.
For India, the policy challenge is consequently more sophisticated than merely counting the number of firms.
Regulators must ask whether concentration produces economies of scale and consumer benefits—or whether it allows firms to acquire excessive market power, raise barriers to entry and weaken competitive pressure.
As India’s economy becomes increasingly capital-intensive, digital and consolidated, understanding oligopoly will become increasingly important not only for economists but also for policymakers, investors, businesses and consumers.
In India’s emerging corporate landscape, the decisive question is no longer simply “How many firms are in the market?” It is “How does each firm behave when it knows that every major rival is watching?” That is precisely the strategic problem that game theory was designed to explain.
Citations
Gregova, E. (2009), [conceptual treatment of oligopoly and imperfect competition].
Piraino Jr., T. (2004), [discussion of strategic interdependence and game theory].
Business Standard (2026), analysis of concentration and oligopolistic characteristics across Indian sectors.
Telecom Regulatory Authority of India (TRAI), 2026 telecom subscription data.
Government of India / PIB, telecom market-share data, May 2026.
DGCA-related June 2026 aviation market data.
Reuters, analysis of the changing competitive structure of India’s paints industry.
ScienceDirect, Cement Market Special: India, analysis of cement capacity concentration.
Grasim Industries, FY26 results and Birla Opus expansion.
Autocar India, 2025 passenger-vehicle market shares.