By Janaina Vilella*
With COP30 just months away, Brazil is taking on a strategic role in the global climate debate, not only as host of the event but also as a key player in the transition to a low-carbon economy. At the center of this process are
The productive sector, which needs to adapt its business models to global climate goals, and the financial and capital markets, which are emerging as key players in financing this transformation. In this scenario, Brazil has a unique opportunity to project itself internationally, leveraging its rich biodiversity to transform environmental assets into financial investments.
One practical example of this agenda's implementation is the approval of the law that established the Brazilian Emissions Trading System (SBCE) in 2024, an important milestone in the creation of a regulated carbon market in the country.
By establishing clear regulatory targets—different from the voluntary market—the system promotes a greater national commitment to decarbonization, with the first negotiations taking place after governance is defined. B3's proactive approach strengthens its position as an infrastructure prepared to support the development of carbon trading in both the voluntary and regulated markets, directly contributing to the climate transition. In 2024, 3.3 million carbon credits were registered and traded on the platform, resulting from the partnership between ACX Brasil and B3. The initiative combines the robust and regulated infrastructure of the Brazilian stock exchange with ACX's expertise in trading environmental assets to connect project developers and buyers to a reliable, efficient, and globally integrated carbon market.
B3's positioning as a strategic infrastructure for the decarbonization agenda is not new. Twenty years ago, the creation of the ISE B3 (Corporate Sustainability Index) was crucial for market participants to identify the best practices of listed companies. Since then, B3 has expanded its role in this area through initiatives such as the ICO2 B3, an index focused on efficient carbon management. Recently, a methodological review of the ICO2 reduced the portfolio's carbon footprint by 88% by prioritizing companies with better efficiency in the relationship between emissions and revenue. Today, the index includes 61 companies from 23 subsectors and helps provide even greater clarity for investors' decision-making. These companies are attentive and committed to the efficiency of their greenhouse gas (GHG) emissions. Within the portfolio, 92% of the companies already map the risks and opportunities of climate change for their business. To offset their emissions, 77% of the companies use carbon credits, and 97% have their inventories verified by a third party. 72% of the companies participating in ICO2 quantify the financial impacts of their emissions.
In addition to transparency, the economic viability of decarbonization depends directly on technological innovation and financial instruments. In Brazil, we already have concrete examples of this integration. In the fixed income market, thematic bonds stand out as important financial instruments that support the allocation of capital to companies' ESG projects and goals. These products offer investors allocation alternatives that combine financial returns with rigorous sustainability metrics. Thematic bonds respond to the growing demand for impact investing and reinforce B3's role as a catalyst for the transition to a low-carbon economy. B3 has been issuing these assets since 2018, and by August 2025, the stock had over R$140 billion in thematic bonds.
A key aspect of the decarbonization agenda is the use of data to help stakeholders make informed decisions. To facilitate access to this information, B3 developed ESG Workspace, a platform that brings together more than 240 listed companies. By displaying more than 75,000 public ESG data points, the platform provides a comparative basis for companies to advance their journeys, in addition to enabling stakeholders to include these criteria in their investment analyses and assess the evolution of the agenda in the market.
Brazil has unique environmental assets and a capital market with an evolved infrastructure to finance the transition. Accelerating the flow of green capital also depends on effective integration between public policies, regulation, and genuine stakeholder engagement—from regulators to institutional investors. A significant advance in this regard for Brazil, one that we must recognize, is the establishment of sustainable taxonomy rules. This is a fundamental tool for structuring a reliable base of information and criteria, capable of guiding sustainable investments and unlocking concrete financing opportunities for companies with decarbonization goals. B3 is the convergence point for these initiatives. It is where the discourse takes shape, and the necessary structure for the flow of capital occurs with credibility, transparency, and operational excellence.
With COP30 in Belém, we have the chance to broaden the understanding, for all these audiences, that sustainability is not just a value: it is a competitive advantage — and an urgent matter that cannot be postponed.
*Director of Communications and Sustainability at B3
