For thousands of businesses operating in the Golden State, a looming deadline for comprehensive climate reporting is creating a unique kind of compliance tightrope: prepare diligently, but for rules that aren't yet fully defined. California's groundbreaking climate disclosure laws, Senate Bill 253 (SB 253) and Senate Bill 261 (SB 261), require companies to report their greenhouse gas emissions and climate-related financial risks starting in the coming years. Yet, the final regulatory language from the California Air Resources Board (CARB) – the agency tasked with implementation – remains conspicuously absent.
This regulatory limbo is forcing companies to invest significant resources into building out new data collection systems, engaging consultants, and mapping complex supply chains, all without the precise specifications they'll ultimately need to meet. It's a high-stakes gamble, as compliance failures could lead to substantial penalties and reputational damage.
SB 253, known as the Climate Corporate Data Accountability Act, mandates public and private companies doing business in California with over $1 billion in annual revenue to disclose their Scope 1, Scope 2, and Scope 3 greenhouse gas emissions. The first Scope 1 and 2 reports, covering fiscal year 2025 data, are due in 2026, with Scope 3 emissions following a year later. Meanwhile, SB 261, the Climate-Related Financial Risk Act, targets companies with over $500 million in annual revenue, requiring them to report on their climate-related financial risks and mitigation strategies, with initial reports also due in 2026.
"It's a classic chicken-and-egg scenario," explains Maria Chen, a partner at GreenMetrics Consulting, which advises dozens of companies on ESG compliance. "Our clients know these rules are coming, and the scale of data collection, analysis, and verification required means they can't afford to wait. But without the final text from CARB, there's always the risk that their current preparations might miss a critical nuance or require a costly pivot down the line."
The delay stems from CARB's extensive rule-making process, which involves public workshops, stakeholder feedback, and detailed environmental and economic impact analyses. While essential for robust regulation, this deliberative pace puts businesses in a challenging position. Many are proceeding with best available practices, often aligning with established frameworks like the Greenhouse Gas Protocol and the Task Force on Climate-related Financial Disclosures (TCFD) recommendations, hoping these will closely mirror CARB's eventual requirements.
The sheer undertaking of accurately tracking Scope 3 emissions – those generated across a company’s value chain, including suppliers, customers, and employees – is particularly daunting. For a large multinational, this could involve thousands of entities, each contributing to their carbon footprint. Companies are finding themselves needing to educate their entire ecosystems on data collection, a process that can take months, if not years, to mature.
The California legislation isn't operating in a vacuum. It arrives amidst a broader global push for enhanced climate disclosure, including the U.S. Securities and Exchange Commission (SEC)'s own climate disclosure proposals (currently facing legal challenges) and comprehensive regulations in the European Union. This confluence of mandates suggests that robust climate data collection will soon be a non-negotiable aspect of doing business, irrespective of specific state-level delays.
For companies, the current period demands flexibility and a proactive approach. Many are implementing internal carbon accounting systems, conducting preliminary materiality assessments, and engaging third-party verifiers to ensure the integrity of their data. The goal is to build a resilient reporting infrastructure that can adapt once CARB's final rules are published.
"The smart money isn't waiting," says David Miller, Chief Sustainability Officer at Apex Innovations Inc.. "Even with the uncertainty, the market—from investors demanding ESG transparency to customers prioritizing sustainable brands—is already moving in this direction. California's rules are just accelerating an inevitable shift. We're building our reporting capabilities now, not just for compliance, but because it's becoming a fundamental part of our business strategy."
While the final regulations may still be some months away, the message to companies is clear: the clock is ticking. Those that proactively build their capacity for detailed climate reporting, even amidst the current ambiguity, will likely be in a much stronger position when the definitive rules finally land. The cost of waiting, many believe, far outweighs the risk of preparing for what's expected.
