Cono Sur · Digital Markets · Platform Competition · Updated August 2026
Latin America’s Platform Competition Problem: Platform Power vs. Open Rails
Mercado Libre shows how commerce, payments, logistics, credit and advertising can compound inside one private ecosystem. Brazil’s Pix and Open Finance show the opposite force: interoperable infrastructure that can keep parts of digital market access open.
Latin America’s platform competition problem is increasingly a contest between private ecosystem control and interoperable market infrastructure.
Mercado Libre illustrates the first side: commerce, logistics, payments, credit and advertising reinforce one another inside an increasingly integrated ecosystem. Brazil illustrates the second: Pix and Open Finance create interoperable rails that can reduce dependence on a single private channel.
For companies, the business question is therefore wider than market share. It is who controls customer access, transaction flow, ranking, data, fulfillment and the ability to switch channels.
Market Analysis Framework
The regional platform debate has moved beyond theory. Mercado Libre reported US$21.9 billion in Q2 gross merchandise volume, US$101 billion in total payment volume and 88 million fintech monthly active users. The company says users active across both marketplace and Mercado Pago are its fastest-growing segment.
At the same time, Banco Central data show Pix operating at national-infrastructure scale, with more than 170 million individual users, more than 7 billion transactions in May and 889 participating institutions as of 19 August.
The newer signal is Open Finance. On 28 August, Banco Central said the ecosystem had 103 million active authorizations covering 68 million accounts, while payments and transfers through Open Finance moved R$1.16 billion in July. CADE remains active in AI and digital-market cases, while PL 4675/2025 is still under congressional consideration rather than enacted law.
Core market reading:
The most useful distinction is no longer simply “big platform versus small competitor.” It is closed ecosystem advantage versus interoperable market infrastructure. Both can coexist in the same economy, and companies may depend on both.
Platform power is access infrastructure
Digital platforms connect several sides of a market at once: buyers and sellers, merchants and payment users, advertisers and audiences, drivers and passengers, developers and software ecosystems. Once those connections become essential to commercial activity, the platform becomes part of the market’s infrastructure.
That changes the competitive question. A company can face low consumer prices and still be commercially dependent on a marketplace’s ranking, a payment provider’s customer relationship, a logistics network’s service levels or an advertising platform’s data.
In digital markets, market power can sit in the route to the customer rather than in the price of the service.
Mercado Libre shows how ecosystem power compounds
Mercado Libre is now a stronger platform-infrastructure case than it was when this article was first published. In Q2 2026, the company reported net revenues and financial income of US$10.2 billion, gross merchandise volume of US$21.9 billion and total payment volume of US$101 billion.
Its fintech operation reached 88 million monthly active users. The company also reported that users active in both commerce and fintech grew 37% year on year and have been its fastest-growing user segment since late 2023.
The competitive point is the interaction between layers. Marketplace activity can feed payments. Payments can feed credit. Credit can reinforce retention. Logistics improves commerce conversion. Advertising monetizes seller dependence on visibility. Mercado Libre explicitly describes the ecosystem connecting commerce and fintech as difficult to replicate.
Advertising adds another access layer. In Q2, Mercado Libre said it exceeded 10% of Latin America’s digital advertising market for the first time, while deploying AI into seller advertising, marketplace search and ranking.
Pix and Open Finance create a different infrastructure model
Brazil provides an important counterweight to the idea that digital market infrastructure must always be privately integrated. Pix is an interoperable payment rail operated under Banco Central governance and available across a large number of financial institutions and payment providers.
Banco Central data updated in August 2026 show more than 170 million individual Pix users and more than 7 billion transactions in May. As of 19 August, the system listed 889 participating institutions, including banks, cooperatives, payment institutions and payment initiators. This matters for competition because the rail is not owned by one marketplace or one private commerce ecosystem.
Open Finance adds another layer. On 28 August, Banco Central reported 103 million active authorizations involving 68 million accounts. Payments and transfers initiated through the ecosystem moved R$1.16 billion in July. Payment initiation allows a user to authorize a transaction through a service different from the institution holding the account, which can reduce the need for one private platform to own every step between discovery, transaction and payment.
The architecture may also become less purely domestic. In August, Banco Central said it was evaluating connections between Pix and other instant-payment systems abroad. That remains a development agenda rather than an existing cross-border network, but it extends the competitive question from domestic interoperability toward international payment access.
Brazilian signal: Pix does not eliminate private platform power. It changes one part of the bargaining structure by making the underlying payment rail broadly interoperable.
CADE is already testing digital-market power in practice
Brazil’s competition debate is no longer limited to future legislation. In May 2026, CADE reviewed a group of AI and digital-market transactions involving Microsoft, Google, NVIDIA and other technology companies.
CADE required notification of the Microsoft–Inflection transaction and opened procedures regarding Google–Windsurf and Google–Hume AI. The authority emphasized that technology, intellectual property, specialist teams and competitive capabilities can be relevant even when a target has little Brazilian turnover.
That is an important shift for market analysis. Traditional revenue thresholds do not always capture digital relevance. An AI team, a model, a distribution channel or access to a platform can carry strategic value before conventional market-share data show it.
CADE has also acted in platform-access questions involving WhatsApp Business and AI chatbots, reinforcing that access rules inside a dominant communication infrastructure can become a competition issue.
PL 4675/2025 remains the regulatory watchpoint
Brazil’s PL 4675/2025 would create a framework for designating economic agents of systemic relevance in digital markets and imposing special obligations. The bill received urgency status in March 2026 and a preliminary plenary report was presented on July 8.
As of August 30, it has not become law. The Chamber lists the bill as ready for the plenary agenda and awaiting action by the President of the Chamber. Its urgency regime remains in place. On August 12, the Economic Development Committee approved a request for a public hearing on the proposal’s economic impacts.
For companies, the useful signal is therefore not “Brazil has adopted a DMA.” It has not. The signal is that active CADE enforcement and a broader ex-ante digital-market framework are developing in parallel.
The EU DMA is now a comparison, not the center of the story
The European Union’s Digital Markets Act remains useful because it gives language to gatekeeper power, contestability, interoperability and data portability. But Latin America does not need to be read as a delayed copy of Europe.
Brazil already has its own institutional combination: a competition authority working on digital and AI cases, a legislative debate on systemic digital actors, Pix as interoperable payments infrastructure and Open Finance as an architecture for data and payment initiation.
The relevant comparison is therefore which regulatory and infrastructure tools actually keep digital markets contestable in each country.
Uruguay shows that platform analysis is regional
Uruguay remains useful as a smaller-market example. Its taxi and Cabify-related competition case applied two-sided-market and indirect-network-effect reasoning to local ride intermediation.
The value of the case is not its size. It shows that platform dependency, exclusivity and network effects can matter in small South American markets as well as in Brazil. A company’s practical channel risk can be locally concentrated even when the platform is globally diversified.
Why platform dependency matters for commercial access
For an international company, a market can have attractive demand and still be difficult to reach independently. In e-commerce, marketplaces may dominate discovery and conversion. In payments, a company may depend on local rails and acquirers. In food delivery, mobility or app ecosystems, distribution can be controlled by a small number of intermediaries.
The practical analysis therefore starts with channel architecture: who controls discovery, transaction, payment, fulfillment, reputation, advertising and after-sales access? Then comes dependency: what can be moved elsewhere, and at what cost?
This is a commercial-access question, not only a legal one. A platform can be compliant and still create substantial bargaining dependence for suppliers, sellers or service providers.
What companies should watch
Three business questions that require deeper research
My reading is that Brazil now shows the strongest South American example of two digital-market models developing at the same time.
Mercado Libre demonstrates how private ecosystem depth can increase: commerce, payments, credit, logistics and advertising reinforce one another. Pix and Open Finance demonstrate the opposite institutional logic: payment and data infrastructure can be designed so that many banks, fintechs and merchants connect to common rails.
The 28 August Open Finance figures make that distinction more concrete. More than 100 million active authorizations and measurable payment volume mean interoperability is no longer only a regulatory concept. But open rails do not automatically remove platform dependence. Discovery, ranking, logistics, advertising, credit and customer data can remain concentrated even when payment itself is interoperable.
For companies, the useful question is therefore layer by layer: where is access open, where is it privately controlled, and which dependency would actually be expensive to replace?
Where Published Information Stops
Public sources can show platform scale, regulatory actions, payment statistics, headline fees, product launches and published seller terms. They rarely show the complete commercial dependency of a specific company or sector.
The missing layer is often operational: channel-level conversion, negotiated fees, ranking exposure, seller-service quality, data access, API constraints, account-management practices, logistics performance, alternative-channel economics and the real cost of switching.
Those gaps require targeted channel mapping, seller or merchant interviews, partner research, transaction-flow analysis and direct validation with companies operating inside the ecosystem.
Focused Econosur research modules
- Banco Central do Brasil — Pix: more than 170 million individual users and more than 7 billion transactions in May 2026.
- Banco Central do Brasil — Pix statistics: 889 participating institutions as of 19 August 2026 and participant structure by institution type.
- Banco Central do Brasil — Open Finance five-year update, 28 August 2026: 103 million active authorizations, 68 million connected accounts and R$1.16 billion of payments and transfers in July.
- MercadoLibre Q2 2026 shareholder letter / SEC filing: US$21.9 billion GMV, US$101 billion TPV, 88 million fintech MAUs, ecosystem engagement and more than 10% share of Latin American digital advertising.
- CADE — AI and digital-market cases: Microsoft/Inflection, Google/Windsurf and Google/Hume AI proceedings.
- CADE — Meta and WhatsApp: platform-access and AI-chatbot competition context.
- Câmara dos Deputados — PL 4675/2025: current status, urgency regime, preliminary plenary report and August public-hearing request.
- European Commission — Digital Markets Act: external comparison for gatekeepers, interoperability and contestability.
- Uruguay MEF — Defensa de la Competencia: institutional competition-policy context.
- Reuters — Pix international integration, 10 August 2026: independent reporting on Banco Central’s move toward possible links with foreign instant-payment systems.
- Evidence note: Banco Central, MercadoLibre, CADE and Câmara sources establish the reported scale, enforcement actions and legislative status. The distinction between private ecosystem control and interoperable rails — and the layer-by-layer dependency framework used here — is Econosur analysis.
- Econosur analysis updated 30 August 2026.
Need to know where a platform controls commercial access?
Public market data can show demand and platform scale. The harder question is where a company becomes dependent on a marketplace, payment rail, ranking system, logistics network or customer-data owner.
Econosur researches platform structure, channel concentration, payment infrastructure, partner economics, switching constraints and regulatory exposure for defined South American business questions.
Discuss a platform research questionFrequently asked questions
What is Latin America’s platform competition problem?
The problem is increasingly a contest between private ecosystem control and open or interoperable market infrastructure. Market power can sit in marketplaces, payment rails, logistics, rankings, data and customer relationships rather than only in price or market share.
Why does Pix matter for platform competition in Brazil?
Pix matters because it is a large interoperable payment rail. Banco Central data in August 2026 show more than 170 million individual users, more than 7 billion transactions in May and 889 participating institutions as of 19 August, giving companies and consumers payment infrastructure that is not tied to one private commerce platform.
Why is Mercado Libre a platform-infrastructure case?
Mercado Libre combines commerce, logistics, payments, credit and advertising. In Q2 2026 it reported US$21.9 billion in GMV, US$101 billion in total payment volume and 88 million fintech monthly active users, showing how several layers of market access can reinforce one ecosystem.
What is Brazil doing about digital market power?
Brazil is combining active competition enforcement by CADE with a legislative debate around PL 4675/2025. CADE has already examined AI and digital-market transactions involving Microsoft, Google and other technology companies, while the bill remains under congressional consideration.
Why is Uruguay relevant to platform competition?
Uruguay is useful as a smaller-market case because its competition authority has applied two-sided-market and network-effect reasoning to ride intermediation. It shows that platform competition analysis is relevant beyond the largest Latin American economies.
What should companies research before relying on a platform channel?
Companies should map customer access, payment rails, data ownership, ranking and advertising control, logistics dependence, switching costs, interoperability, alternative channels and regulatory exposure before assuming that digital demand is independently reachable.
