ISSB Launches Nature Disclosure Consultation as California's GHG Deadline Looms
A Big Week for Sustainability Disclosure Regulation
Two significant climate and environmental disclosure developments landed within days of each other, putting corporate sustainability teams on high alert heading into late October 2026.
ISSB Opens Nature-Related Disclosure Consultation
The International Sustainability Standards Board (ISSB) launched a public consultation on October 22, 2026, on proposals to guide companies in disclosing their nature-related financial risks, according to Investment Executive. The move had been anticipated since April, when the ISSB's board meeting in Beijing settled on an IFRS Practice Statement — a non-mandatory guidance document — as the vehicle for nature-related disclosures, rather than amending IFRS S1 or S2 or creating a standalone standard.
The IFRS Foundation confirmed the exposure draft was timed to coincide with COP17 of the Convention on Biological Diversity, currently under way in Yerevan, Armenia, followed by a 120-day consultation period. The proposed Practice Statement draws heavily on the Taskforce on Nature-related Financial Disclosures (TNFD) framework, focusing on dependencies on natural systems, ecosystem impacts, and their translation into financial risk. ISSB Chair Emmanuel Faber has been explicit that this is not a softer path: companies subject to IFRS S1 are already required to disclose material nature-related risks, and the Practice Statement is designed to show them how. More than 44 jurisdictions have adopted or are adopting ISSB standards, meaning the consultation's outcome will carry global weight.
California's November 10 SB 253 Deadline Is Now Binding
On the domestic front, the California Office of Administrative Law approved the California Air Resources Board's (CARB) initial climate disclosure regulation on October 12, 2026, effective immediately, cementing November 10, 2026 as the first hard deadline for Scope 1 and Scope 2 greenhouse gas emissions reports under SB 253, as reported by Proskauer Rose and confirmed by Akin Gump. SB 253 covers U.S.-organized companies with more than $1 billion in annual revenue that do business in California — encompassing both public and private entities.
The final rule, noted by Thompson Hine, codifies first-year relief: companies may base their 2026 report on emissions data they already held or were collecting as of December 5, 2024, or may alternatively file a statement of non-reporting on company letterhead. Scope 3 reporting is not required until 2027. Meanwhile, enforcement of SB 261's climate-related financial risk disclosure requirements remains suspended pending a Ninth Circuit appeal, leaving that parallel obligation in legal limbo.
The Broader Regulatory Picture
These developments unfold against a backdrop of diverging global trajectories. In Europe, the CSRD Omnibus I reforms — formally published in the EU Official Journal in February 2026 — slashed the revised ESRS mandatory datapoint count by roughly 61% and raised the reporting threshold to companies with at least 1,000 employees and €450 million in turnover. The revised ESRS entered into force on November 10, 2026, applying to financial years beginning January 1, 2027. At the federal level in the U.S., the SEC has proposed to rescind its 2024 climate disclosure rules entirely, citing authority and cost concerns, leaving California as the de facto mandatory disclosure regime for large companies operating in the United States.