California's age verification law (AB 1043), explained

The short answer

AB 1043, the Digital Age Assurance Act, was signed on October 13, 2025 (Chapter 675, Statutes of 2025) and passed with no votes against. It is codified at California Civil Code sections 1798.500 to 1798.505.

It took effect January 1, 2026, but its duties start January 1, 2027. A 2026 amendment, AB 1856 (Chapter 184, Statutes of 2026, signed September 10, 2026), changes several parts of it from January 1, 2027.

What operating systems must do

At account setup, an operating system provider must ask the account holder to enter the user's birth date, age, or both. The provider then makes an age signal available to apps through a real-time interface. After AB 1856, this duty applies only where the operating system has an account setup feature.

• The signal gives an age range, not a birth date. At a minimum, it must show which of four ranges the user is in: under 13, 13 to under 16, 16 to under 18, or 18 or older.
• Providers must send only the minimum information needed and may not share the signal with third parties for purposes the law does not require.
• For devices set up before January 1, 2027, providers must offer the age-entry screen before July 1, 2027.

What app developers must do

A developer must request the age signal when its app is downloaded and launched. A developer that receives the signal is treated as knowing the user's age range, even if it ignores the signal. The signal is the main indicator of age unless the developer has clear and convincing information showing otherwise.

• Developers may not request more information than needed or share the signal with third parties for purposes the law does not require.
• For apps last updated on or after January 1, 2026 and downloaded before 2027, developers that have not yet requested a signal must do so before July 1, 2027.
• After AB 1856, app stores must request the signal from the operating system and pass it to developers on request.
• After AB 1856, an entity covered by the law may not prompt a user to change their age information, and no one may request a signal unless this law or another law requires it.
• After AB 1856, a developer's actual knowledge also covers its own websites where users create accounts or log in, and developers do not have to request a new signal at every login, though they may request one periodically.

Is it ID-based age verification?

No. The age comes from what the account holder enters at setup, passed along as a range. The law does not require document checks or face scans, and it says it does not require collecting more personal information. That sets it apart from laws that require ID-based verification.

Who enforces it, and the penalties

Only the California Attorney General can enforce it, in a civil action. Penalties are up to $2,500 per affected child for each negligent violation and up to $7,500 per affected child for each intentional violation, plus injunctions. There is no private right to sue and no cure period.

Operating systems and app stores that make a good-faith effort are not liable for an incorrect signal or for how a developer uses it. AB 1856 adds a similar good-faith protection for developers.

What AB 1856 changed

• It removes from the definition of operating system provider anyone who distributes an operating system or app under license terms that let recipients copy, redistribute and modify the software. This appears aimed at open-source licenses, though the text does not use the words open source.
• It ties the developer duty to apps offered through a covered app store, and it narrows what counts as an application.
• It treats age information an account holder gives for a subaccount as clear and convincing information.
• It takes effect January 1, 2027, the same day the original duties begin.

How chatbots use it

The law has no chatbot-specific section. A chatbot offered as an app through a covered app store appears to fit its definitions of application and developer, so the age signal would reach chatbot apps like any other app. Whether a chatbot used only on the web is covered is less clear after AB 1856, which ties the developer duty to app stores.

California's companion chatbot law, SB 1119, builds on it. From January 1, 2027, a companion chatbot operator must either determine users' ages under the Digital Age Assurance Act or apply its child protections to all users. If an operator cannot determine a user's age through the Digital Age Assurance Act, it must rely on the age determination made under California's addictive-feed law (Health and Safety Code section 27001).