Arkansas has become the second state to pass a law requiring social media platforms to verify the ages of their users. Governor Sarah Huckabee Sanders has signed the “Social Media Safety Act” into law, which requires companies verify the ages of users under 18 and to gain parental consent before minors create new accounts.

Utah recently passed similar measures, which also impose strict rules on how social media platforms handle the accounts of their youngest users, including an age verification requirement. The laws are part of a growing movement to enforce age verification measures and other age-based restrictions for social media companies. At least three other states are currently considering similar legislation.

The laws are also controversial. While lawmakers have for years called for more protections for teens on social media, privacy advocates and civil rights groups have opposed age verification mandates. Likewise, some child safety groups have argued that comprehensive privacy legislation would be a more effective way to protect children.

Under the Arkansas law, slated to take effect in September, companies are required to check the ages of their users via government-issued IDs like a driver’s license or “any commercially reasonable age verification method.” But, as CNN notes, it’s not entirely clear which companies will be forced to comply with the law. The legislation includes a number of exemptions that would seem to excuse some prominent platforms.

For example, it states that platforms focused on “professional networking” and “career development” are exempt, which would seem to be a direct reference to LinkedIn. It also has exceptions for gaming-focused companies, as well as companies that allow “a user to generate short video clips of dancing, voice overs, or other acts of entertainment in which the primary purpose is not educational or informative,” which could be interpreted as excluding TikTok.