California’s Proposition 65 (“Prop. 65”), the Safe Drinking Water and Toxic Enforcement Act of 1986, requires, among other things, sellers of products to provide a “clear and reasonable warning” if use of the product results in a knowing and intentional exposure to one of more than 900 different chemicals “known to the State of California” to cause cancer or reproductive toxicity, which are included on The Proposition 65 List. For additional background information, see the Special Focus article, California's Proposition 65: A Regulatory Conundrum.

Because Prop. 65 permits enforcement of the law by private individuals (the so-called bounty hunter provision), this section of the statute has long been a source of significant claims and litigation in California. It has also gone a long way in helping to create a plaintiff’s bar that specializes in such lawsuits. This is because the statute allows recovery of attorney’s fees, in addition to the imposition of civil penalties as high as $2,500 per day per violation. Thus, the costs of litigation and settlement can be substantial.

The purpose of Keller and Heckman’s latest publication, Prop 65 Pulse, is to provide our readers with an idea of the ongoing trends in bounty hunter activity. 

In September of 2025, product manufacturers, distributors, and retailers were the targets of 520 new Notices of Violation (“Notices”) and amended Notices, alleging a violation of Prop. 65 for failure to provide a warning for their products. This was based on the alleged presence of the following chemicals in these products. Noteworthy trends and categories from new Notices sent in September 2025 are excerpted and discussed below. A complete list of all new and amended Notices sent in September 2025 can be found on the California Attorney General’s website, located here: 60-Day Notice Search.