Mysten Labs CTO Sam Blackshear joins Anthropic

Mysten Labs cofounder and chief technology officer Sam Blackshear said on Aug. 6 that he is leaving the Sui developer to join Anthropic for defensive security research. Summary Sam Blackshear is leaving Mysten Labs to join Anthropic for defensive security research involving AI. Evan Cheng will assume Mysten’s technical vision while continuing as the blockchain company’s chief executive. Blackshear plans to remain an adviser to Mysten Labs and developers across the Sui ecosystem. Move’s creator said a foundation is being developed and he intends to remain involved afterward. Anthropic is expanding defensive cyber research as frontier models improve software vulnerability discovery capabilities rapidly. Blackshear announced the move in posts on X, saying the role would let him return to hands on technical work while studying a new problem area. He did not disclose his starting date, reporting line or specific projects at Anthropic. When I reflect on my career, I have been happiest doing hands-on technical work while exploring new problem domains. This is an opportunity to do both, and I’m motivated to work on security at a time when the balance of power between attackers and defenders is shifting. — Sam Blackshear (@b1ackd0g) August 5, 2026 Blackshear said he was motivated by a period in which the “balance of power between attackers and defenders is shifting.” The comment is his assessment, not a measured industry result. However, Anthropic’s recent research supports the broader concern. The company said Claude Opus 4.6 could identify high severity software vulnerabilities at scale, while its Frontier Red Team studies how advanced models could strengthen defense and offensive activity. You might also like: Sui’s Mysten Labs starts preorders for new gaming console: report Blackshear will remain involved with Mysten and Sui Blackshear said he would remain a close adviser to Mysten Labs and respond to Sui ecosystem builders who seek his help. Mysten’s leadership page identified him as a cofounder and CTO before the announcement, alongside cofounder and chief executive Evan Cheng. Blackshear said Cheng will now set the company’s technical vision, although Mysten had not published a separate succession statement. The departing executive credited Cheng with recruiting many of Mysten’s strongest technical employees and noted his previous leadership experience at Apple and Meta. Blackshear also thanked Mysten Labs staff and the wider Sui community. His advisory role may provide continuity, but the company has not disclosed whether it will appoint another CTO or redistribute his duties. Mysten was founded by former Meta engineers and became the original contributor to the Sui layer one blockchain. Mysten Labs partnered with Google Cloud to use generative AI in code development and auditing. The collaboration included tools trained on Move and an AI based auditing system designed to identify vulnerabilities in Move, Rust, TypeScript and Solidity code.