Anthropic PBC has reportedly acquired Coefficient Bio Inc., a provider of artificial intelligence software for medical researchers.

Half the startup’s stock was owned by a healthcare-focused venture capital firm called Dimension. The fund informed investors of the acquisition in a letter that was published today by journalist Eric Newcomer. According to the document, Anthropic is paying more than $400 million in stock for the company.

Coefficient was founded about eight months ago by a group of former pharmaceutical executives and researchers. According to Newcomer, the company developed AI models optimized for biology research. In a January post on X, one of the company’s co-founders stated that the company’s technology would “change everything about how the industry learns and makes decisions.” That hints that Coefficient’s models are built to automate particularly high-impact research tasks.

One of the most important medical research workflows to which startups are applying AI is small molecule discovery. Small molecules are biological building blocks about one nanometer in size that form the basis of most pharmaceuticals. Manas AI Inc., a startup active in that area, estimates AI can speed up certain aspects of the discovery workflow by a factor of 100.

One way researchers determine whether a small molecule has therapeutic applications is by checking its ability to dock to pathogens. If a small molecule can’t dock to a pathogen, it can’t neutralize it. The evaluation process is time-consuming because biological molecules regularly change their shape, which means that their docking surfaces change as well. AI can speed up the task.

Startups are also applying the technology to many other clinical research tasks. Bioptimus Inc., for example, has released a transformer model that makes it easier to study biomarkers. Those are molecules that can be used to diagnose disease and measure treatment effectiveness. The tech industry’s largest players have also joined the fray with AI models that speed up tasks such as mapping out the properties of proteins.

Anthropic’s decision to acquire a healthcare-focused AI startup is not entirely surprising. Last year, the company introduced a feature bundle that improved Claude’s ability to automate medical research tasks. In January, it added integrations with several third-party clinical databases and research tools.

Anthropic may follow up its recent healthcare-focused updates with features geared toward researchers in other fields. Last month, the company launched a blog focused on the scientific applications of Claude. OpenAI Group PBC’s recently disclosed plan to launch a “fully automated researcher” may give Anthropic another reason to build new scientific features.

Coefficient is the third company Anthropic has bought in the past six months. It previously acquired task automation startup Vercept Inc. and the developer of Bun, a popular open-source tool for building JavaScript applications.

Image: Anthropic