California’s Climate Corporate Data Accountability Act is accelerating the shift towards comprehensive, standardised emissions reporting, with implications for multinational companies and US policy landscape.
California’s SB-253 is moving from concept to compliance, and the shift is already being felt well beyond the state. The law, formally known as the Climate Corporate Data Accountability Act, requires companies doing business in California with more than $1 billion in annual revenue to report greenhouse gas emissions, beginning with Scope 1 and Scope 2 data, followed by Scope 3 disclosures later. The California Air Resources Board said on 26 February 2026 that it had approved the initial regulation needed to implement the programme and set 10 August 2026 as the first reporting deadline for Scope 1 and Scope 2 emissions. (leginfo.legislature.ca.gov)
That timetable matters because California is not simply creating another state filing. SB-253 reaches entities doing business in California, not just companies headquartered there, which means the rule can extend to a large share of national and multinational groups with operations or sales in the state. The legislative text defines covered reporting entities as businesses with annual revenues above $1 billion that do business in California, and it requires disclosures to follow Greenhouse Gas Protocol standards. (leginfo.legislature.ca.gov)
The result is a regulatory model that could reshape corporate reporting across the United States. Large companies rarely maintain separate carbon-accounting systems for one state alone, so once California sets a disclosure standard, it tends to become a practical baseline elsewhere. That is especially true in a fragmented U.S. policy environment where state rules increasingly fill the gap left by the absence of a single federal sustainability-disclosure framework. (leginfo.legislature.ca.gov)
The biggest operational challenge is likely to be Scope 3, which covers upstream and downstream emissions outside a company’s direct control. California’s bill text says those disclosures begin in 2027, while the first year of reporting is limited to Scope 1 and Scope 2. Scope 3 is often the most difficult category to measure because it depends on supplier engagement, customer-use data and estimation methods across the value chain. (leginfo.legislature.ca.gov)
That complexity helps explain why the law has become more than a compliance exercise. Companies now need reliable internal systems, clear methodology and external assurance to avoid reporting gaps. Under the statute, reporting entities must obtain independent third-party assurance, and the rules also require emissions reporting in line with the Greenhouse Gas Protocol. CARB has said the regulation is intended to establish clear and consistent disclosure requirements and to give investors and consumers access to reliable information. (leginfo.legislature.ca.gov)
There is also a wider legal and strategic context. Nixon Peabody said in a March 2026 update that CARB’s rules were approved despite ongoing litigation, leaving some uncertainty for businesses about how and when they must report. The firm said SB-253 is still moving forward, while related climate-risk reporting under SB-261 remains tied up in court. (nixonpeabody.com)
For many companies, the immediate question is no longer whether climate disclosure will become more demanding, but whether they have the internal capability to respond. The shift favours organisations that can translate regulation into data systems, supplier engagement and management decisions. In that sense, SB-253 is not just a reporting law. It is a test of whether companies can turn emissions tracking into a core business function.
- https://cse-net.org/california-sb253-climate-law-us-shift/ – Please view link – unable to able to access data
- https://leginfo.legislature.ca.gov/faces/billNavClient.xhtml?bill_id=202320240SB253 – This official California legislative page provides the full text of Senate Bill 253, known as the Climate Corporate Data Accountability Act. The bill mandates that entities doing business in California with annual revenues exceeding $1 billion disclose their greenhouse gas emissions, including Scope 1, 2, and 3 emissions. The disclosures must conform to the Greenhouse Gas Protocol standards and are to be publicly filed with the California Air Resources Board (CARB). The reporting requirements for Scope 1 and 2 emissions begin in 2026, with Scope 3 disclosures starting in 2027. The bill also outlines the verification process for these disclosures and the penalties for non-compliance.
- https://www.bsigroup.com/en-US/insights-and-media/insights/blogs/californias-new-climate-disclosure-updates-sb-253–sb261/ – This article from BSI discusses the enactment of California’s Climate Corporate Data Accountability Act (SB 253) and the Greenhouse Gases: Climate-Related Financial Risk Act (SB 261). It details the requirements for companies operating in California to disclose their greenhouse gas emissions and climate-related financial risks. Starting in 2026, companies with substantial California revenue must begin reporting, with smaller companies in larger corporations’ supply chains needing to provide climate data to support the Scope 3 emissions reporting requirement, which begins in 2027. The article also highlights the applicability of these laws to all companies that do business in California and exceed specific revenue thresholds.
- https://kpmg.com/us/en/articles/2023/ca-climate-laws-ghg-emissions-and-risk-reporting-reg-alert.html – KPMG’s article provides an overview of California’s climate disclosure laws, including SB 253 and SB 261. SB 253 requires entities doing business in California with annual revenues exceeding $1 billion to publicly disclose their greenhouse gas emissions, including Scope 1, 2, and 3 emissions. SB 261 mandates that entities with at least $500 million in annual revenue disclose their climate-related financial risks and the measures adopted to reduce and adapt to those risks. The article also notes proposed amendments to these laws that would change the relevant reporting year from 2026 to 2028.
- https://www.nixonpeabody.com/insights/alerts/2026/03/02/california-climate-disclosure-laws-update – This alert from Nixon Peabody LLP discusses the current status of California’s climate disclosure laws, SB 253 and SB 261. It notes that the California Air Resources Board (CARB) approved the regulations implementing these laws on February 26, 2026. The article also mentions ongoing litigation and a pending injunction, creating ambiguity for businesses about whether, when, and how they have to report. It provides key compliance considerations for businesses and outlines the requirements of both SB 253 and SB 261.
- https://www.nixonpeabody.com/insights/alerts/2025/07/14/california-climate-disclosure-and-reporting-requirements-take-shape – This alert from Nixon Peabody LLP outlines the greenhouse gas emission reporting requirements under SB 253. It details the reporting timeline, noting that regulated businesses must report Scope 1 and 2 emissions beginning in 2026 (based on 2025 emissions data), and Scope 3 emissions beginning in 2027. The article also discusses the assurance requirements, stating that Scope 1 and 2 data must be verified by an independent third party with limited assurance starting in 2026 and at a reasonable assurance beginning in 2030.
- https://www.whitecase.com/insight-alert/california-climate-disclosure-laws-carb-approves-greenhouse-gas-reporting-and-climate – This alert from White & Case LLP discusses the California Air Resources Board’s (CARB) approval of the California Greenhouse Gas Reporting and Climate Financial Risk Disclosure Initial Regulation for SB 253 and SB 261. The article notes that CARB adopted the regulation on February 26, 2026, and provides insights into the key provisions of the regulation, including the requirements for entities to disclose their greenhouse gas emissions and climate-related financial risks.
Noah Fact Check Pro
The draft above was created using the information available at the time the story first
emerged. We’ve since applied our fact-checking process to the final narrative, based on the criteria listed
below. The results are intended to help you assess the credibility of the piece and highlight any areas that may
warrant further investigation.
Freshness check
Score:
8
Notes:
The article was published on April 30, 2026, which is recent. However, the content closely mirrors information from other sources dated February 2026, raising concerns about originality. ([ww2.arb.ca.gov](https://ww2.arb.ca.gov/news/carb-approves-climate-transparency-regulation-entities-doing-business-california?utm_source=openai))
Quotes check
Score:
7
Notes:
The article includes direct quotes from the California Air Resources Board (CARB) dated February 26, 2026. While these quotes are recent, they are not independently verified within the article, and no external sources confirm their accuracy.
Source reliability
Score:
6
Notes:
The article originates from cse-net.org, which is not a widely recognized news organization. This raises concerns about the credibility and independence of the source. Additionally, the article appears to be summarizing information from CARB’s official communications without providing independent analysis or verification.
Plausibility check
Score:
7
Notes:
The claims about California’s SB-253 law and its implications are plausible and align with known legislative developments. However, the lack of independent verification and reliance on a single source diminishes the overall credibility.
Overall assessment
Verdict (FAIL, OPEN, PASS): FAIL
Confidence (LOW, MEDIUM, HIGH): MEDIUM
Summary:
The article presents information about California’s SB-253 law, but it heavily relies on summarizing CARB’s official communications without providing independent analysis or verification. The source, cse-net.org, is not widely recognized, and the lack of independent verification from other reputable news organizations raises concerns about the credibility and reliability of the content. ([ww2.arb.ca.gov](https://ww2.arb.ca.gov/news/carb-approves-climate-transparency-regulation-entities-doing-business-california?utm_source=openai))