Last Wednesday, Anthropic announced that earlier this year it had launched a molecular biology lab, where Claude agents read and conjecture about hard biology problems and human scientists run experiments on what they report. This AI-powered lab, the company said, had made its first discovery.

What Anthropic says its system of 950 agents found after 21 hours was not a brand-new sequence. The agents flagged a repeating pattern surrounding a known enzyme, a particular pattern Anthropic said hadn’t been catalogued before. These claims have angered some biologists. A viral post from one, subsequently endorsed by the chair and CEO of the drugmaker Eli Lilly, said that “finding a weird cluster of genes and repeats is often the easy part.”

Muddying the issue further, Mario Rodríguez Mestre, a biologist at the University of Copenhagen, said over the weekend that his team had already discovered this particular pattern. Mestre, who regularly chatted with Claude in his work, wondered whether Anthropic’s team had learned from his conversations. Anthropic denies this, but Mestre says he’s stopping all use of Claude anyway.

Part of the problem is that AI companies insist the systems are making discoveries themselves. To some, that is incompatible with how science works. It’s also making people more skeptical of genuine progress when it happens. Earlier this month, OpenAI said its agents had cracked a million-dollar problem in mathematics, but skeptics questioned whether the result was the one mathematicians care most about.