# Anthropic: Internal Claude Model Designed 17 Lab-Confirmed Binders Against Scorpion Neurotoxins; Partner Citrini Is Pitching Life-Sciences Stocks

Times of AI Desk · 2026-10-20 · Research

[https://timesof.ai/2026/10/anthropic-claude-scorpion-neurotoxin-binders-citrini-17-of-211](https://timesof.ai/2026/10/anthropic-claude-scorpion-neurotoxin-binders-citrini-17-of-211)

> Anthropic says an internal research model designed 318,484 protein binders against scorpion neurotoxins; 17 of 211 lab-tested designs met its binder criteria. It does not claim an antivenom. Quartz relays Citrini Research's account that prompting required a biosecurity-classifier exemption at Anthropic's offices; Citrini is now backing life-sciences stocks.

A frontier model ran most of a binder-design loop, and the outside partner is an investment firm pitching stocks on the result. **Anthropic** published on **Tuesday, October 20** results from a campaign in which an **internal research model**, working inside Claude Science, designed small protein binders against scorpion neurotoxins. Over **64 hours**, with four follow-up prompts developed with **Citrini Research**, Claude generated **318,484** designs and selected **180** for testing; Anthropic's team added **31** more. Contract labs **Adaptyv Bio** and **Twist Bioscience** tested all **211**, and **17** met Anthropic's criteria for a binder — each against a **single** toxin. None of the multi-toxin designs met the criteria for more than one toxin.

Anthropic says it has **not** tested the binders for neutralisation in cells or animals and **does not claim** to have produced an antivenom. The campaign used on the order of **10,000 GPU hours**. Anthropic is releasing all 211 designs and their data.

## Partner conflict and the classifier account

The project was run with **Citrini Research**, a financial investment research firm. **Quartz** reports Citrini's account that prompting took place at Anthropic's offices because Citrini's request to **bypass a biosecurity classifier** required security measures it lacked. That detail is Citrini's, relayed by Quartz; Anthropic's research post does not mention a classifier exemption.

Quartz, citing **Bloomberg**, says Citrini is now backing life-sciences stocks including **Charles River Laboratories**, **Revvity** and **Tecan** off the result. Citrini's stock pitch is a conflict of interest for any framing of the science as market-moving.

## What the lab found

Anthropic targeted five neurotoxins (Cn2, Ts1, AaH I, AaH II, LqhIII). The two strongest designs, both against Mexican scorpion toxin **Cn2**, bound in the **single-digit nanomolar** range and appear to compete with a known neutralising antibody (LR), Anthropic says. Binding was measured by SPR at both CROs under Anthropic's hit criteria (KD ≤ 1 µM, no off-target signal against CLEC12A). Outside experts Susana Vázquez Torres and Timothy P. Jenkins called the work a promising first step in Anthropic's post.

## Limits

- No neutralisation or in vivo efficacy data; not an antivenom claim.
- Biosecurity-classifier detail is Citrini via Quartz, not Anthropic's post.
- Citrini is an investment firm pitching stocks on this result.

## Sources

- [Anthropic: How Claude designed protein binders against scorpion neurotoxins (October 20, 2026)](https://www.anthropic.com/research/claude-scorpion-toxin-binder-design)
- [Quartz: Citrini Research is backing life sciences stocks after using Claude to design proteins (October 20, 2026)](https://qz.com/citrini-research-life-sciences-stocks-claude-protein-design-102026)