Sam Blackshear, the co-founder and chief technology officer of Mysten Labs, announced on August 6 that he is leaving the company to join Anthropic as a defensive security researcher. Blackshear, who created the Move programming language while at Meta, will step away from day-to-day operations at the Sui blockchain developer but will remain an advisor to both Mysten Labs and a yet-to-be-launched Move Foundation.
Evan Cheng, Mysten Labs’ co-founder and CEO, will now set the company’s technical vision, absorbing Blackshear’s former responsibilities. Blackshear praised Cheng’s track record at Apple and Meta and attributed Mysten’s strong technical team to his recruitment efforts. The company has not disclosed whether it plans to appoint a new CTO.
Anthropic’s growing focus on AI-driven cybersecurity threats motivated Blackshear’s move. The firm recently reported that its Claude Opus 4.6 model could identify high-severity software vulnerabilities at scale, and its Frontier Red Team is examining how advanced models could be used both offensively and defensively. Blackshear’s background in programming languages and automated bug finding aligns with Anthropic’s defensive research agenda.
“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,” Blackshear wrote on X.
The broader crypto market showed mixed signals at the time of the announcement, but the transition highlights an increasing intersection between AI security and blockchain technology. Mysten Labs itself had already partnered with Google Cloud on AI-powered code auditing tools for Move, Rust, and Solidity, signaling an existing interest in this crossover.
Blackshear confirmed that a Move Foundation is “in the works,” aiming to provide neutral governance for the language’s development across multiple blockchains. However, no launch date, leadership structure, or funding details were provided. The announcement comes amid ongoing discussions about smart contract safety—a $260 million exploit on Cetus Protocol, which runs on Sui, demonstrated that even a secure programming language cannot prevent all application-level vulnerabilities.
Traders will monitor how Blackshear’s departure affects Sui’s technical roadmap and whether the Move Foundation can build momentum under his advisory. Meanwhile, Anthropic’s defensive security unit gains a researcher with deep expertise in static analysis and language design.
