Google is building a crypto custody tool for Wall Street that splits control of private keys across institutions — and embeds a policy engine that can block transactions before they happen.
The product, called Google Multi-Party Compute, is being tested by major financial institutions and is set for commercial release in early 2027. The same banks that froze Canadian truckers' accounts and pressured platforms to cut off dissidents are now positioning themselves as the gatekeepers of decentralized finance. Regulators — who have spent years harassing independent crypto projects — are conspicuously silent.
Here is how it works: MPC fragments a private signing key and distributes the pieces across separate systems. No single party holds the full key. A bank might keep one share on its own hardware, another sits in Google Cloud, a third with a rival provider. Transactions require a threshold of fragments — two-of-three, five-of-seven — to sign. That much is standard multisig security.
The catch is the policy engine. Before any signature is executed, a rules system running inside Google's Confidential Space checks the transfer against limits, destination restrictions, and approval rules. Google says it has no access to key shares in unencrypted form, per CoinDesk. But the architecture places Google's infrastructure at the decision point for every transaction.
Google Cloud's MPC Symposium in New York this week features speakers from Morgan Stanley, Citi, and Wells Fargo, according to Cointelegraph — the same Wall Street firms that spent years badmouthing crypto now muscling in to control how it gets accessed.
The security pitch is real, and the industry has a genuine key-management problem. Chainalysis attributed 43.8% of cryptocurrency stolen in 2024 to compromised private keys. DeFiLlama data shows roughly 40% of the $16.69 billion lost to hacks through June came from key compromises. In June, an attacker grabbed seven keys from one developer's computer during the Humanity Protocol breach and drained wallets across two networks. Bitcoin Magazine reported that incident in detail.
But the cure and the disease share a symptom: concentration of authority. The whole point of decentralized finance was to remove the gatekeeper. Now Google and the custody market it is entering — led by Fireblocks, Fordefi, and BitGo — are building a new one. Google argued to CoinDesk that its banking relationships and security expertise give it an advantage. It also positions itself as a neutral supplier for banks that do not want to rely on competitors. A neutral supplier that runs the policy engine approving or denying every transaction.
Rich Widmann, Google's director of digital assets strategy, told CoinDesk that "regulated financial institutions begin adopting blockchains and tokenization" and "need scalable, proven infrastructure to secure their clients' assets." Note the framing: clients' assets, not your assets. The institution holds the fragments. The institution sets the rules. You get access at their pleasure.
Google is also dangling AI and quantum-computing threats as marketing leverage. Chainalysis found scams linked to AI tool vendors averaged $3.2 million per operation in 2025. Google researchers estimated a future quantum machine could derive a bitcoin private key from an exposed public key in about nine minutes. No AI system has broken wallet cryptography. No quantum computer of that power exists. Google says its architecture can adopt post-quantum signatures later without forcing institutions to rebuild. No timetable set.
The technology is not the problem. The structure of control is. Every fragment held by a bank or a cloud provider is a point where a government subpoena, a compliance directive, or a political freeze order can be executed. The same infrastructure that secures the key can be told to stop signing transactions to the wrong address — or the wrong cause.
The question is not whether Google's system works. It is who holds the fragments — and who gets to say no when you try to move your own money.
