Watershed bets disclosure rules make carbon accounting a must-buy; $100M Series C at $1.8B

Enterprise software that measures a company's full carbon footprint (scope 1-3), produces audit-ready sustainability reports, runs emissions-reduction programs, and offers a marketplace for carbon credits and clean-power purchases.

Carbon disclosure would move from voluntary pledges to mandatory, audit-grade reporting — turning carbon accounting into a compliance must-buy.

Series C of $100M at a $1.8B valuation in February 2024, led by Greenoaks; total disclosed funding $239M per CNBC.

Watershed was founded in San Francisco in 2019 by Christian Anderson, Taylor Francis and Avi Itskovich, engineers from Stripe who saw that companies making net-zero pledges had no rigorous way to measure them. At its Series B in 2022 its customers managed an estimated 20 million tonnes of CO2e. The founding bet was that climate disclosure would follow the same path as financial accounting — voluntary at first, then legally required.

The mandate arrived on schedule. The EU's Corporate Sustainability Reporting Directive made 2024 the first year of government-mandated climate disclosure for nearly 12,000 companies, and California's SB 253, signed in 2023, set its first emissions-reporting deadline for 2026. In February 2024 Watershed raised a $100M Series C led by Greenoaks at a $1.8B valuation — the most valuable climate software company — with customers including General Mills, Carlyle, BBVA, Paramount, Block and four of the top six US banks, whose operations it said managed an estimated 479 million tonnes of CO2e, up more than 10x in a year.

Still scaling as of September 2026: in May 2025 Watershed made its CEDA emissions database free as Open CEDA; in October 2025 it launched AI-accelerated SB 261 climate-risk reporting and a Guaranteed Assurance program for SB 253; and in August 2026 it was marketing tools for the law's first filing deadline of November 10, 2026, with 70 of the Fortune 500 among its in-scope customers.

Companies with net-zero pledges had no rigorous way to measure emissions, and regulators were clearly heading toward mandatory disclosure.

The EU CSRD (first reporting year 2024) and California SB 253 (first filing November 2026) turned voluntary climate accounting into a legal obligation for thousands of companies.

Ex-Stripe founders applied fintech-grade data engineering to emissions, and the 2023 CEDA acquisition gave Watershed proprietary multi-regional emissions data.

Watershed's $100M Series C at a $1.8B valuation showed investors agreed that disclosure mandates would create a durable software category.

Its customers' managed emissions growing to an estimated 479 million tonnes of CO2e gave the platform scale and lock-in ahead of the filing deadlines.

When a regulation is clearly coming, build the product the deadline will force companies to buy — and make the data solid enough to survive auditors once the law lands.

As of September 2026, Watershed is scaling ahead of the deadlines it bet on: California's SB 253 first filings are due November 10, 2026, Scope 3 reporting and limited assurance follow in 2027, and Watershed sells AI-accelerated SB 261 reporting plus a Guaranteed Assurance program for SB 253 (waiving up to $250,000 in fees if a customer fails third-party verification). It also opened its CEDA emissions database to the public as Open CEDA in May 2025, with Amazon, WWF and PCAF as endorsers, and continues to serve enterprise customers including 70 of the Fortune 500.