Who Holds the Keys?

When I was a young officer, I learned that no armoury opens to one man. There were two keys, held by two people, and the door stayed shut until both were present. Nobody thought it insulting. Nobody thought it inefficient. It was simply how you made sure that the most dangerous things in the building stayed exactly where they were meant to be.

Finance learned the same lesson. More slowly, and at considerably greater expense.

The wall that keeps the fire out

Over the best part of a century, traditional markets pulled their critical functions apart and put each one in a different pair of hands. One party executes the trade. Another clears it, netting exposures and standing between the counterparties. A central securities depository records who owns what. A custodian holds the assets, segregated from its own balance sheet and ring-fenced from its creditors. Auditors check the lot.

To the impatient eye, it looks like an expensive way of doing something simple. It is not. Each separation is a firebreak. When an institution fails, as institutions occasionally do, the fire stops at the wall. The client's assets were never the custodian's assets. They were never available to the custodian's creditors. They are still there in the morning.

One roof, one key

Then came digital assets, and with them a seductive idea. Why pay for all those intermediaries when code can do the job?

The centralised exchanges that dominate the market answered by putting everything under one roof. Trading, clearing, custody and settlement, all in-house. Client deposits pooled in wallets the exchange controls. Ownership recorded not on the blockchain, but on the exchange's own internal ledger. A trade "settles" when a database entry changes.

It is fast. It is elegant. And it rebuilds, inside a single entity, precisely the concentration of risk that traditional finance spent decades dismantling. It is the armoury with one key, and the man who holds it also keeps the register.

The bill arrives

We know how that story ends, because we watched it in 2022. When FTX collapsed, the problem was not volatility. Volatility is simply the weather in this market. The problem was that customers discovered they did not own what they thought they owned. Trust evaporated. Global trading volumes halved, and stayed subdued through most of the following year.

What brought the institutions back is the most instructive part of the whole affair. Not a new token. Not a better app. Separation. Serious participants stopped leaving their assets on exchanges. They held them with independent, regulated custodians and mirrored their collateral onto the trading venue. In other words, they rebuilt the wall by hand.

The middleman returns

There is a rich irony here, and I confess I rather enjoy it. An industry founded on the promise of abolishing the middleman has spent the past few years quietly reinventing him. Prime brokers to tame fragmented collateral. Independent custodians to hold the keys. OTC desks performing the checks a clearing house once performed as a matter of course.

The regulators have noticed. Under MiCA, crypto-asset service providers in Europe must segregate client assets and submit to independent audit. In the UK, the FCA has proposed holding client cryptoassets in trust to protect them on insolvency, with the full regime due in October 2027. Strip away the vocabulary and you will find the same principles that govern a custodian bank in Frankfurt or a depository in Brussels.

The new world is being fitted with the old world's plumbing. Not because regulators lack imagination, but because the plumbing works.

No one to telephone

Digital assets add one further complication, and it is not a small one. They are bearer instruments. Whoever controls the private key controls the asset, and a transaction on the chain cannot be reversed. There is no back office to telephone, no failed settlement to unwind, no court that can reach into the ledger and put things right.

The industry's best answer is, once again, the armoury door. Multi-signature wallets that need more than one key to move anything at all. Multi-party computation that splits a key into fragments, so that no single device ever holds it whole. Two keys. Two people. The soldier and the banker would both recognise it instantly.

The first question

So here is the point, and it reaches well beyond crypto.

Asset safety is not a back-office matter. It is the first question any allocator should ask, and too often the last one they think about. Before you ask what an asset will return, ask who holds it. Ask whether it is segregated, and from whom. Ask what happens to it on the morning the institution holding it does not open its doors. Ask who can move it, and how many of them it takes.

Tokenisation, digital securities and on-chain settlement are coming into the mainstream, and they will bring genuine benefits. Speed. Transparency. Markets that never sleep. But every one of those innovations rests on the same question that has governed custody since the first bar of gold was locked in a vault.

At Thomas Murray, we have spent three decades inside the plumbing of the world's market infrastructure, assessing the custodians, depositories and settlement chains on which the system depends. The technology has changed beyond recognition. The question has not changed at all.

Who holds the keys?