California enacts law enabling people to universally opt out of data sharing (therecord.media)

California Gov. Gavin Newsom signed a bill requiring web browsers to provide an easy-to-find, one‑click mechanism that lets Californians universally opt out of third‑party data sales. The measure builds on the CCPA’s 2018 right to send opt‑out signals but is the first U.S. law to obligate browsers (previously users relied on extensions or privacy‑focused browsers) to expose a push‑button control that emits a universal opt‑out instead of forcing repeated per‑site decisions. The package also includes separate bills to make social media account cancellation and full data deletion simpler and to strengthen disclosure under the state’s Data Broker Registration Law. For the AI/ML community this tightens the supply of personal third‑party data commonly used for model training, profiling, and ad targeting. Expect reduced access to some types of web‑aggregated personal data and greater legal compliance burden for data pipelines that ingest brokered datasets, increasing demand for privacy‑preserving approaches (synthetic data, federated learning, differential privacy), provenance auditing, and stronger consent mechanisms. The law is likely to accelerate shifts toward first‑party data strategies and safer data practices by platforms and researchers, while complicating efforts that rely on large-scale personal data collection without explicit, durable opt‑out signals.