Guide
California Prop 65: Safe-Harbor Warnings, the 2025 Short-Form Rule and Bounty-Hunter Defence
California's Safe Drinking Water and Toxic Enforcement Act of 1986 — Proposition 65 — requires businesses with ten or more employees to provide a 'clear and reasonable warning' before knowingly and intentionally exposing California consumers to any of the 900+ chemicals OEHHA has listed as known to the state to cause cancer, birth defects or reproductive harm. Enforcement is unique: in addition to the Attorney General, any private citizen acting in the public interest can sue, and 'bounty-hunter' law firms drive the majority of Prop 65 actions, with settlements averaging $50,000–$150,000 per complaint. The 2018 'clear and reasonable' regulations and the 2025 amendments to the short-form warning have reshaped what counts as compliant. This guide is written for QA, regulatory and counsel at brands selling consumer goods into California.
Start free trial Free trial, no credit card, onboard in days, not months.
The list, the listing mechanism and the safe-harbor levels
OEHHA (the Office of Environmental Health Hazard Assessment) maintains the Prop 65 list, updated approximately monthly. Substances are listed via four mechanisms: the State Qualified Experts panels, authoritative bodies (US EPA, IARC, NTP, FDA, NIOSH), labour code listings (federally listed carcinogens), and Health and Safety Code listings. Each substance has either a No Significant Risk Level (NSRL, for carcinogens) or a Maximum Allowable Dose Level (MADL, for reproductive toxicants), or both. Below the NSRL/MADL, no warning is required ('safe-harbor' exposure). Above the safe-harbor level, a 'clear and reasonable' warning is required. Brands without a per-SKU exposure assessment against the relevant NSRL/MADL are operating on assumption, not compliance.
The safe-harbor warning content and format (2018 rules)
27 CCR § 25600 et seq. (effective 2018) sets the safe-harbor warning format: the yellow warning triangle (▲), the word 'WARNING' in bold capital letters, the name of at least one listed chemical for each endpoint (cancer, reproductive, or both), the URL www.P65Warnings.ca.gov, and the language requirement (any language in which other product information is provided on the label must also carry the warning). The full warning is required on consumer-product labels unless the short-form is used. Warnings on websites and in catalogues must appear before purchase, not only on the product detail page. The recurring failure is a generic 'cancer and reproductive harm' warning without naming a specific chemical — that no longer qualifies for safe harbor.
The short-form warning and the 2025 amendments
OEHHA's short-form warning, in use since 2018, allowed a condensed warning ('WARNING: Cancer and Reproductive Harm — www.P65Warnings.ca.gov') without naming the chemical. In December 2024 OEHHA finalised amendments effective 1 January 2025 (with a three-year transition to 1 January 2028 for existing products) tightening the short-form: it now requires naming at least one chemical, must be in a specified font size, and is permitted only on products with packaging total surface area of five square inches or less where the long-form would not fit. Catalog and internet warnings using the short-form must now also name the chemical. Brands still using the 2018 short-form on larger packaging are operating on an expiring transitional permission.
Online, catalog and B2B disclosures
Prop 65 warnings must appear before the consumer is exposed — which for online sales means before the consumer purchases or otherwise commits. 27 CCR § 25602(b) requires the warning on the product display page (not buried in a footer) or, where the warning is by hyperlink or rollover, in a manner that ensures the consumer encounters it before purchase. Amazon and eBay carry their own Prop 65 attribute fields that propagate to the product detail page; failing to populate them is a frequent bounty-hunter trigger. For B2B sales of consumer-product components, the upstream supplier should provide the listed-substance disclosure to the downstream brand so the brand can make the warning decision; written supplier declarations are the recommended practice.
The 60-day notice and bounty-hunter litigation pattern
A private plaintiff must serve a 60-day notice on the business, the California Attorney General and the local district attorney before suing under Prop 65. The Attorney General publishes 60-day notices weekly; brands receiving a notice typically have 60 days to evaluate, settle or correct. Settlements ordinarily include a per-substance payment to the plaintiff, an attorney-fee component (often the largest line), and an injunctive relief term requiring future warnings or reformulation. Total settlement value averages $50,000–$150,000 per complaint, with high-volume bounty-hunter firms (CERT, As You Sow, Bursor & Fisher, Tucker Ellis-defended plaintiffs) generating most of the volume. Defending on safe-harbor exposure data is the cheapest defence — but it requires the data to exist before the notice arrives.
A 45-day Prop 65 readiness path
Days 1–10: substance scan — pull the current OEHHA list against the bill of materials for every SKU sold into California; flag SKUs with any listed substance present at non-trace levels. Days 11–25: per-SKU exposure assessment for flagged SKUs against the relevant NSRL/MADL; document the safe-harbor decision or commit to warning. Days 26–35: artwork refresh for SKUs requiring a warning — 2018 long-form content, post-2025 short-form rules; online/catalog warning placement audit. Days 36–45: bounty-hunter readiness — document the exposure file location, train customer service and legal on 60-day notice response, freeze baseline.
Where this lives in V5 Ultimate
The clauses above aren't theoretical — every one maps to a shipped module and an industry profile. Jump to the parts of the product that turn this guide into evidence on a Monday morning.
Modules that do the work
Industries this hits hardest
Frequently asked
We have fewer than ten employees — are we exempt?
Yes for the warning duty — Prop 65 applies to businesses with ten or more employees. However, your upstream suppliers and downstream customers may still impose Prop 65 contractual obligations on you. And the discharge prohibitions of Prop 65 (separate from the warning duty) apply regardless of size. Document the employee count if you intend to rely on the exemption; 60-day notices have been served on businesses that crossed the threshold without realising.
Does a 'WARNING: This product contains chemicals known to the State of California to cause cancer and reproductive harm' suffice?
Not for safe harbor since 2018. The 2018 regulations require the warning triangle, the word 'WARNING' in bold capitals, at least one named chemical per endpoint, and the URL www.P65Warnings.ca.gov. The pre-2018 generic warning is no longer safe-harbor compliant. The 2025 short-form amendment further tightened the chemical-name requirement for the short-form. Defending a non-safe-harbor warning is possible but expensive; safe-harbor formats are the cheapest path.
How do we know which substance to name?
Choose a substance that is present in the product above the safe-harbor level (or that you cannot demonstrate is below). Most brands name the substance with the lowest NSRL/MADL relative to the product's content, because that substance drives the warning duty. Document the choice and the supporting analysis in the exposure file. Naming a substance not actually present at exposure-relevant levels is itself a basis for a 60-day notice.
Is Prop 65 enforceable against products sold outside California?
Prop 65 applies to exposures occurring in California. If you sell into California from another state via the internet or wholesale, the warning duty applies. If you sell only outside California with effective geo-filtering, Prop 65 generally does not apply — but document the geo-filtering. Amazon and Walmart treat 'available to ship to California' as triggering the warning; setting California shipping restrictions without warnings is itself a moderate-effort defence that some bounty hunters challenge.
See it on your shop floor.
Free trial, no credit card, onboard in days, not months.
Related reading
Spot something off? .