The law mandates that device operating systems and app stores require users to enter their age or date of birth when setting up a new phone or computer. The new rules are slated to take effect on January 1st, 2027, and for devices set up prior to that date, the OS provider — like Apple or Google — must come up with a way for users to enter their ages by July 1st that year. Negligent violations of the law could cost such companies up to $2,500 per child impacted, and intentional violations could go up to $7,500 per child. The law still shields the companies from liability for “erroneous” age signals as long as they make a good faith effort to comply.

“We’ve seen some truly horrific and tragic examples of young people harmed by unregulated tech, and we won’t stand by while companies continue without necessary limits and accountability,” Newsom said in a statement on signing the bill, along with a raft of other legislation related to children’s online safety, including a requirement to add warning labels to social media. “We can continue to lead in AI and technology, but we must do it responsibly — protecting our children every step of the way. Our children’s safety is not for sale.”

California’s new rules are the latest in a wave of new age assurance laws sweeping the country. Utah became the first state to pass an app store age verification law, followed by Texas and Louisiana. Meta notably broke from tech peers to support such bills, which put the onus on app stores run by Apple and Google, rather than developers like itself. But they were initially pushed by parent advocates who have become some of the leading voices in passing a range of kids safety laws in the US.

AB 1043 notably gained support from not only Meta, but also Google, which would likely be regulated under the act. Google senior director of government affairs and public policy Kareem Ghanem called it “one of the most thoughtful approaches we’ve seen thus far to the challenges of keeping kids safe, recognizing that it’s a shared responsibility across the ecosystem,” in a statement included in a press release by the Democratic assemblymember who led the bill, Buffy Wicks.

Unlike some of the other laws, the California measure does not require parental consent for app downloads. It also doesn’t force users to upload sensitive documents like government IDs, which caused uproar in the UK over the implementation of the Online Safety Act (OSA).

But the bill still lacks some key stakeholder support. Apple has not gotten behind the bill like its peers, and the Motion Picture Association (MPA), which advocates for the film and television industry, urged lawmakers to reject the bill, according to Politico, because it might create confusion among streaming accounts where parents and kids have different profiles. Wicks told Politico she’d work to fine-tune outstanding concerns with the bill next year.