CA SB 253: As November 10 deadline approaches, CARB issues letter to potentially covered entities, plaintiffs remind Ninth Circuit of pending decision

One of the two landmark climate-disclosure laws California enacted in 2023 has its first reporting deadline in just over two weeks, amid continued uncertainty regarding its constitutionality.  

In 2023, the California Legislature enacted SB 253, the Climate Corporate Data Accountability Act; and SB 261, the Climate-Related Financial Risk Act. These laws require large publicly- and privately-held entities doing business in California to disclose information on their direct and indirect greenhouse gas emissions and their climate-related financial risks. After years of regulatory process and amid litigation challenging the constitutionality of these laws, in summer 2026 the California Air Resources Board revised its proposed regulations defining key terms concerning applicability of SB 253 and SB 261 and implementing the fee assessment program. Earlier this month, the California Office of Administrative Law approved those regulations.  

Alongside the formal rulemaking process, CARB has issued multiple rounds of guidance, indicating how it will be exercising enforcement discretion for the first reporting year (2026), clarifying the type of information CARB is expecting for this first reporting round, and explaining how entities that intend to avail themselves of CARB’s enforcement discretion should respond. The most significant recent update was in September 2026 when CARB opened an intake platform and issued related guidance. And in October, as it awaited OAL action, CARB issued a “courtesy” letter to entities “that may meet the criteria for reporting to ensure that they are aware of upcoming deadlines and available resources.”  

For now, the most important deadline is November 10, when covered entities must report their Scope 1 and 2 greenhouse gas emissions under SB 253. 

In parallel, interested parties have been awaiting action from the U.S. Court of Appeals for the Ninth Circuit, which held oral arguments in January 2026 on an appeal of a denial of a preliminary injunction against the laws. The Ninth Circuit has stayed implementation of SB 261 pending the outcome, but not SB 253. On October 8, the plaintiffs sent a letter to the court notifying of recent events and reiterating their request for an injunction.   

Crowell & Moring continues to monitor and advise regarding updates on these matters; please reach out to the authors with any questions. To receive more information on this and our other alerts, please see this link.