Google is previewing a crypto custody system that several banks are testing before a planned commercial launch in early 2027. Google is reportedly presenting Google Multi-Party Compute today in New York during Google's first digital assets symposium. Several financial institutions have access through a private preview. CoinDesk reported that Alphabet has begun using the system to protect Alphabet's assets. Google has not announced pricing.
The system uses multi-party computation to divide a signing key into fragments distributed among different parties or machines. Transaction signing requires a specified number of those fragments, without ever reconstructing the complete key in a single location. A bank could distribute shares among the bank's hardware, Google Cloud and another cloud provider. Institutions can choose signing thresholds, including two-of-three and five-of-seven. A policy engine within Google's Confidential Space evaluates transfer limits, permitted destinations and approval requirements before a signature is produced. CoinDesk reported that Google says Google cannot access unencrypted key shares.
Chainalysis attributed 43.8% of cryptocurrency stolen during 2024 to private-key compromises. DeFiLlama data attributes approximately 40% of the $16.69 billion lost in hacks through June to compromised keys. An attacker obtained seven keys from a single developer's computer in the June Humanity Protocol breach and emptied wallets on two networks. These breaches demonstrate that concentrating signing authority creates a single point of failure. The industry has consequently recommended multi-vendor multisignature arrangements that distribute control among hardware and software providers.
Google also presents the system as protection against fraud enabled by AI. Chainalysis found that scams associated with AI tool vendors averaged $3.2 million per operation in 2025. Other scams averaged $719,000 per operation, according to Chainalysis. The Chainalysis report associates the figures with AI involvement but does not establish that AI caused the difference. Ethereum researcher Justin Drake has warned that AI might eventually discover mathematical shortcuts capable of weakening wallet signatures. No AI system has demonstrated that ability. Google's MPC design addresses credential theft and unauthorized transfers, rather than a failure of the underlying cryptography.
Quantum computing poses a distinct risk over a longer horizon. Google researchers estimated that a sufficiently powerful future quantum computer could calculate a bitcoin private key from an exposed public key in about nine minutes. Approximately 6.9 million bitcoin have public keys that are exposed. Google says the architecture can accommodate post-quantum signatures later without requiring institutions to rebuild existing systems. However, Google has provided no schedule for that capability.
Google is entering a market in which Fireblocks, Fordefi and BitGo are leading providers. Google argued that Google's relationships with banks and security expertise provide a competitive advantage. Google also presents the company as a neutral provider for banks seeking to avoid dependence on competitors. Banks already employ specialized platforms, including BNP Paribas's custody arrangements with Metaco and vaults developed with BitGo for multiple institutions.