California climate rules spark digital debate
On 19 March, XBRL US submitted comments to the California Air Resources Board (CARB) as part of its consultation on implementing Senate Bills 253 and 261, California’s landmark climate disclosure laws.
These new programmes will require large companies operating in California to report both emissions and climate-related financial risks.
SB 253 mandates annual scope 1, 2, and eventually scope 3 emissions disclosures from businesses earning over $1 billion, while SB 261 calls for biennial climate risk reports from entities with revenues over $500 million. CARB is currently developing rules to enforce these laws, and the XBRL US response urged the Board to adopt digital, structured reporting in line with the Greenhouse Gas Protocol and TCFD—and crucially, in XBRL format.
It’s a pivotal moment. With global regulators moving fast to digitise climate disclosures, the US cannot afford to fall back on static PDFs and narrative guesswork. As XBRL US noted, tagging sustainability data in machine-readable formats isn’t optional, it’s essential. A good story isn’t enough to assess climate risk disclosures. We need verifiable numbers, structured data, and a level playing field.
Digital reporting isn’t about complexity. It’s about clarity. Standardisation. Comparability. If California gets this right, it can lead the charge toward trustworthy, tech-ready sustainability reporting. If not, we risk a patchwork of half-measures and opacity.
Read the full XBRL US comment letter here.
