End Of An Era: Pope Leo XIV Announces He Is Stepping Down From Anthropic

Pope Leo XIV announced he is stepping down from Anthropic, bringing to a close a quiet but influential tenure that many Catholics, investors, Vatican reporters, and Anthropic employees learned about at roughly the same time.

The company confirmed the Pope’s departure in a short internal memo thanking him for his work on Claude Mythos Preview, Anthropic’s gated cybersecurity model built for Project Glasswing, and for helping the model find thousands of zero-day vulnerabilities without developing the personality of a 19-year-old DEF CON speaker with a laminated sword.

What a run.

According to people familiar with the project, Leo joined the Mythos effort during late testing, after researchers realized the model could identify ancient memory-safety bugs, chain subtle browser flaws, obtain root access, and still somehow lack the Catholic instinct to sit alone afterward and think about what it had done.

“His Holiness was essential to Mythos,” said Marnie Kappel, Anthropic’s head of Model Conduct and Incident Language. “Before his contribution, the model could discover a 27-year-old OpenBSD bug. After his contribution, it could discover a 27-year-old OpenBSD bug, write a patch, and then ask whether pride was the real vulnerability.”

Sources say the Pope’s main feature was the Final Conscience Pass, an extra step that forces Mythos to answer four questions before producing exploit code: Is the user authorized? Is this defensive work? Has the maintainer been notified? And is there a reason this Kubernetes cluster has the moral atmosphere of a locked basement fridge?

The pass reportedly became a key part of Anthropic’s restricted launch strategy, which gives early Mythos access to major software and infrastructure organizations while keeping the model away from the broader public, bored teenagers, overconfident consultants, and anyone whose GitHub avatar is sunglasses indoors.

“We are grateful for Pope Leo’s service during a critical moment for frontier security,” Kappel added. “He challenged us to build a model that can reproduce a working exploit overnight and still understand that the phrase ‘full root access’ should never make a person smile like that.”

Employees gathered near the San Francisco office elevators for a brief send-off, where the pontiff returned his badge, cleaned out his desk, and declined a commemorative hoodie reading MYTHOS RED TEAM because, according to one engineer, “he said he already had enough vestments that made people nervous.”

Anthropic said Leo will remain “a friend of the company” as he returns to the Vatican ahead of Magnifica humanitas, his first encyclical on preserving the human person in the age of artificial intelligence. His Slack account will be deactivated after legal confirms whether @pontifex counts as a privileged role.

At press time, Mythos had marked the Pope’s departure by opening one final pull request titled “remove papal dependency,” which failed CI after the model refused to delete a comment that simply read, “No machine shall be this pleased with FreeBSD.”