Researcher Claims 1 Bitcoin Bounty for Achieving Largest Quantum Attack on Underlying Technology

The theoretical threat of a quantum attack on bitcoin's security has become more tangible. Quantum security startup Project Eleven awarded a 1 bitcoin bounty, worth approximately $78,000, to independent researcher Giancarlo Lelli for breaking a 15-bit elliptic curve key on publicly accessible quantum hardware. This achievement marks the largest public demonstration of its kind, posing a potential threat to bitcoin, ether, and other major blockchains. Elliptic curve cryptography, which enables crypto wallets to prove fund ownership without revealing private keys, is vulnerable to quantum computer attacks using Shor's algorithm. Although Lelli's result is significant, it does not imply that bitcoin is on the verge of being compromised, as it uses 256-bit elliptic curve security. The prize aimed to assess the progress of quantum attacks on real-world cryptography-based products. Lelli's 15-bit result represents a 512-fold increase over the previous 6-bit demonstration by Steve Tippeconnic in September 2025. Theoretical estimates suggest that the resource requirements for a full 256-bit attack are decreasing rapidly, with a Google Research paper estimating the cost to be below 500,000 physical qubits. Project Eleven CEO Alex Pruden noted that the winning submission came from an independent researcher using cloud-accessible hardware, highlighting the growing concern for wallets with publicly visible keys, which account for approximately one-third of the total bitcoin supply. To address this issue, bitcoin developers have proposed migration paths, including BIP-360, which would introduce quantum-safe address types.