Market Definition in Competition Law: Adapting to the Challenges of the Digital Economy

Defining the relevant market lies at the very core of competition law. It determines the boundaries within which competitive behaviour is examined and forms the basis for assessing anti-competitive agreements, abuse of dominance, and mergers. By delineating the arena of competition, market definition identifies the competitive constraints shaping firm conduct, enabling regulators to assess dominance, anti-competitive behaviour, and merger impacts.

In the traditional economy, identifying market boundaries was relatively straightforward—based largely on pricing and substitutability. However, in the modern digital economy, online platforms operate across multi-sided markets, use data as a key input, and compete on parameters like innovation, privacy, and service quality. These features challenge the adequacy of traditional tests and demand new analytical tools.

This paper examines whether market definition remains the most critical step in competition analysis. It contrasts the approach in offline and online markets, explores key case laws from India and abroad, and evaluates how digitalisation, data, and consumer behaviour are reshaping the concept of the “relevant market.”

Market Definition in Competition Law:

Market definition traditionally consists of two main dimensions:

1. Relevant Product Market (RPM): All products or services considered interchangeable by consumers based on features, price, or intended use.
2. Relevant Geographic Market (RGM): The area where competition conditions are uniform and distinct from other regions.

Sections 2(r), 2(s), and 2(t) of the Competition Act, 2002 codify these concepts in India. The SSNIP test (Small but Significant Non-transitory Increase in Price) is used to determine substitutability—asking whether consumers would switch to another product if prices rose slightly.

Market definition is thus the first and most critical step in dominance assessment, as it establishes the boundaries within which market share and concentration are measured.

Is Market Definition the Most Crucial Step?

Arguments for its importance:

1. Foundation for Dominance Analysis: Without identifying the relevant market, it is impossible to determine whether a firm holds market power or is engaging in anti-competitive conduct.
2. Legal Certainty: Clear boundaries give firms and regulators predictable parameters for compliance and enforcement.
3. Economic Analysis: Market share, entry barriers, and concentration ratios (HHI, CR4) all depend on accurate market delineation.

Arguments against overemphasis:

1. Digital Complexity: In multi-sided, data-driven platforms, market boundaries blur. Consumers often use multiple platforms simultaneously, making substitution uncertain.
2. Direct Effects Evidence: Modern analysis can focus on competitive harm—like foreclosure, predatory pricing, or exclusionary conduct—without defining the market rigidly.
3. Risk of False Negatives: Overly narrow or flawed definitions may let powerful digital firms escape scrutiny, as seen in Big Tech cases.

Hence, while market definition remains vital, it is no longer sufficient alone. In the digital age, effects-based analysis must complement market delineation.

Market Definition in Offline Distribution:

In traditional, offline markets, defining the relevant market remains straightforward and reliable.

• Hoffmann-La Roche v Commission (1979): The European Court of Justice held that dominance must be assessed within a clearly defined substitutable market.
• MCX Stock Exchange Ltd v National Stock Exchange (India, 2011): The CCI defined the market narrowly as “stock exchange services in currency derivatives,” enabling an accurate finding of NSE’s dominance and predatory conduct.

Offline markets involve tangible products, measurable switching costs, and primarily price-driven competition, making classical tools effective.

While traditional markets relied on observable price and output indicators, online markets introduce intangible dynamics—data, attention, and algorithmic visibility—requiring regulators to redefine how competition is measured.

Market Definition in Online Distribution:

Online markets complicate traditional analysis due to:

1. Multi-Sided Platforms: For instance, Google Search operates simultaneously in online advertising, app ecosystems, and user attention markets.
2. Zero-Price Services: Users pay with data, not money, making the SSNIP test less effective. The SSNDQ test (Small but Significant Non-transitory Decrease in Quality) is now proposed to assess competition. However, quantifying ‘quality’ reductions—such as privacy loss or degraded user experience—remains methodologically challenging, highlighting the need for evolving empirical tools.
3. Network Effects and Lock-In: The more users a platform has, the more valuable it becomes, often leading to “tipping” and early dominance.

Key Cases:

• Matrimony.com v Google (India, 2018): The CCI found Google abused dominance in online search advertising. The decision looked beyond price effects to include innovation, fairness, and consumer choice.
• United States v Microsoft (2001): The Court defined the relevant market as PC operating systems for Intel-compatible PCs, recognising Microsoft’s dominance despite the existence of Apple and Linux.
• FTC v Meta (Facebook) (2021): The US court rejected the FTC’s vague definition of “personal social networking services,” insisting on clearer boundaries.

These cases show how regulators worldwide are adapting market definition to suit the complex nature of digital competition.

Role of Data and Consumer Behaviour:

In digital markets, data and user behaviour are central to competitive analysis. Cases such as Matrimony.com v Google (India) and FTC v Meta (US) highlight how market power depends not only on pricing but also on data control, algorithmic influence, and network effects.

Similarly, Google Shopping (EU, 2017) and Amazon Marketplace (ongoing) demonstrate that consumer search patterns and access to seller data shape competition. Investigations into Apple’s App Store in the US and EU further underscore how high switching costs and platform dependence restrict competition.

Thus, competition authorities must now integrate data flows, consumer behaviour, and multi-homing (use of multiple platforms) into market analysis.

Comparing Online and Offline Distribution:

For example, defining WhatsApp solely as a “messaging service” ignores its role in payments, e-commerce, and business communication—highlighting how narrow definitions can distort enforcement.

Globalisation and Cross-Border Challenges:

Digital platforms operate globally, often affecting multiple jurisdictions simultaneously. Conduct by firms like Amazon, Google, or Meta can trigger investigations in the EU, US, and India at the same time. This poses risks of inconsistent findings, forum shopping, and conflicting remedies.

Hence, global convergence in market definition principles has become essential. Institutions such as the International Competition Network (ICN) and Organisation for Economic Co-operation and Development (OECD) play key roles in harmonising global standards and ensuring coherent cross-border enforcement.

The OECD’s 2022 report on Competition in Digital Markets and the ICN’s work on market definition emphasise harmonisation to prevent regulatory divergence and uncertainty for global platforms.

India, with one of the world’s fastest-growing digital ecosystems, faces the dual challenge of encouraging innovation while preventing monopolistic gatekeeping by dominant platforms.

Making Digital Market Rules Smarter – The Way Forward for India:

To keep up with the fast-changing digital world, India’s Competition Commission (CCI) should improve how it studies online markets. Here’s how:

1. Use Smarter Tools: Don’t rely only on the old SSNIP test (which checks price changes). Also use tools like SSNDQ (which looks at quality), data comparisons, and innovation trends to get a fuller picture of competition.
2. Understand the Bigger Picture: Study how users behave on platforms—can they switch easily? Do they use multiple platforms at once? This helps define markets more realistically.
3. Learn from Global Cases: Look at examples like the EU’s Google Shopping and Amazon Marketplace cases. These focused on how competition was actually affected, not just on strict definitions.
4. Be Clear and Open:

Explain clearly how digital markets are defined. This builds trust and helps businesses and regulators understand the rules.

Bottom Line:

India should use a hybrid approach—keep clear definitions but also stay flexible to real-world situations. This will make competition rules fair, clear, and ready for the digital age.

Key Case Laws:

CCI v. Co-ordination Committee of Artists (2017): The Supreme Court of India said that defining the “relevant market” is the first and most important step before checking if a company is dominant or harming competition.

CCI v. Bharti Airtel (2019): The Court highlighted the need for a clear and specific market definition in telecom cases, where different technologies often overlap.

Google Shopping (EU, 2017): This case showed how the European Union began using an effects-based approach—looking at the real impact on competition rather than just rigid market boundaries.

Re Queensland Co-operative Milling Association (Australia, 1976): An early and influential case that introduced the SSNIP test (Small but Significant Non-Transitory Increase in Price), a method still used to define markets today.

Together, these cases show how competition law around the world is moving toward a more flexible and evidence-based way of defining markets—especially in fast-changing, technology-driven industries.

 Policy Implications:

The evolving nature of digital markets demands that competition authorities modernise their analytical capabilities. The Competition Commission of India (CCI) should invest in building specialised expertise in digital economics, data analytics, and algorithmic behaviour to better understand complex market dynamics.

Collaboration with global regulators such as the European Commission (EU), Federal Trade Commission (FTC), and UK Competition and Markets Authority (CMA) can promote consistency and information sharing in cross-border cases.

Additionally, integrating AI-based data tools into market analysis can help the CCI detect collusive patterns, track digital dominance, and assess consumer harm more effectively. These measures will strengthen regulatory agility and ensure that India’s competition regime remains adaptive, transparent, and globally aligned in the digital era.

Conclusion:

In conclusion, market definition continues to anchor competition analysis, but in digital markets, rigid frameworks must yield to more flexible, evidence-based approaches. A hybrid model—combining traditional delineation with behavioural and effects-based analysis—will ensure that competition law remains responsive to the realities of data-driven markets.