But how does one decide what constitutes a piece of content—or whether or not something is considered pornographic?

“It’s mostly a counting question in terms of ‘does the law apply’” Alan Butler, the executive director of Electronic Privacy Information Center, previously told WIRED.

Kupper, who sponsored Arizona’s age verification law, tells WIRED he stuck to the one-third threshold because it’s been previously upheld by the United States Supreme Court. He says he’s heard estimates that 15 to 25 percent of accounts on X are at least somewhat pornographic, but he’s not sure how accurate that is, nor does he think it’s “feasible” to analyze such ratios on every website. X did not respond to questions about what percentage of the platform it considers pornographic.

“I don’t think you should have a threshold. It should be: Do you have pornographic material on your site? OK. I’m not saying you have to age-verify for your entire site, but for any of the pornographic material, you should have to age-verify,” Kupper says. Posts on X that are marked as “age-restricted adult content” can only be viewed by users who are logged in and over the age of 18, though X generally expects users uploading restricted content to mark it as explicit themselves. WIRED wasn’t able to find similar restrictions for pornographic links on the Grok website.

Kupper says in Arizona’s case, individuals would need to bring forth a complaint—for example, if their child was harmed by pornographic material on X—and the court would then have to make X prove that less than one-third of its content is pornographic.

Nebraska state senator Dave Murman, who spearheaded age verification legislation there, tells WIRED he isn’t sure about Grok’s independent site but that “X does not have at least one-third of its content sexually inappropriate or harmful to minors.” However, when asked if the state had measured that, he says it hadn’t—and isn’t aware of any state that had.

“While I would of course prefer a system where every single possible piece of pornographic content is behind an age gate, passing legislation to do so without implicating the valid free-speech rights of social media sites seemed logistically impossible,” he says. “While I don’t know if there is a legislative solution to getting pornography off of social media sites like X, I do hope the company takes action.”

Pornhub, one of the biggest porn sites in the world, has blocked itself from most states with age verification, arguing that there are too many noncompliant sites and that people don’t want to give their ID and personal information to a third-party site to have their ages verified. It will also block itself to new UK users next week on account of the country’s age verification laws, which kicked in last July.

On Tuesday, Solomon Friedman, vice president of compliance for the private equity firm Ethical Partners Capital (ECP), which owns Pornhub’s parent company, Aylo, told WIRED both the methodology and scope of age verification legislation is “fatally flawed.”

He said Google Images, for example, has “thumbnails of every single porn image cached available online.” Friedman and Pornhub want Google, Apple, and Microsoft to enact device-based age verification so that people’s data can stay stored in their phones or laptops.

“That’s also the solution to adult content on quote ‘non-porn’ sites and platforms. It can be used to filter either explicit tweets or posts on X or explicit use of AI chatbots.”

WIRED reached out to Google, Microsoft, and Apple about whether they would be open to device-based age verification but has not yet received a response.