Former SEC Official Warns Quantum Computing Could Break Crypto Security

John Reed Stark, a former official at the U.S. Securities and Exchange Commission, warned that quantum computing advances pose a critical “ticking clock” for cryptocurrency security. The technology threatens to crack the cryptographic foundations that protect Bitcoin and other decentralized networks, he wrote in a social media post. Stark criticized the SEC for not demanding contingency plans from crypto firms, calling the regulator’s silence a failure to prepare for a known risk.

The warning arrives as blockchain infrastructure moves deeper into mainstream finance through spot ETFs, institutional custody, and stablecoin rules. Stark said the quantum threat is real and that regulators should be pressing for post-quantum roadmaps now. Instead, he argued, the agency under Chairman Paul Atkins has focused elsewhere.

The most immediate vulnerability sits in older Bitcoin addresses. According to separate analysis cited by Tom Lee, roughly 30% to 35% of Bitcoin’s circulating supply is held in addresses whose public keys are already exposed on the blockchain. A sufficiently powerful quantum computer could derive the private key from the public key, making those funds spendable by an attacker. Newer address types such as SegWit and Taproot offer better protection, but the older coins remain at risk.

The U.S. government has already set a hard deadline for the shift. An executive order signed by President Trump requires all federal agencies to adopt post-quantum cryptography for key establishment by Dec. 31, 2030, and for digital signatures by Dec. 31, 2031. That timeline gives the crypto industry roughly five years to upgrade critical infrastructure.