The London-based firm provides portfolio, risk-management and trade-data infrastructure to institutional digital-asset firms. Its platform connects with centralized exchanges, custodians, blockchains and decentralized-finance (DeFi) protocols, giving clients a consolidated view of their positions, transactions and risk exposure.

“GSR has not been impacted by any rumored breach,” a company spokesperson said. Bitcoin Suisse, Flowdesk, 3iQ, M2, Ampersan, MNNC and Trovio did not reply to requests for comment before publication time.

A small amount of client funds was stolen, the people said, who spoke on condition of anonymity because the matter is private. Smaller hedge funds with weaker security controls may have been particularly…