What is a Closed-Loop Digital Currency?

Every time a card is tapped in Europe, a share of the payment leaves before it ever reaches the merchant. Visa and Mastercard accounted for roughly 61% of euro area card payments in 2022, according to the European Central Bank, and up to 95% of UK card transactions run on the same two networks. Thirteen euro area countries have no national card scheme at all. The fees taken from each sale are set elsewhere, and the data created by each sale flows elsewhere too.

The call for change is now coming from the top of European finance. Martina Weimert, chief executive of the European Payments Initiative, has called urgently for alternatives to Visa and Mastercard, and ECB President Christine Lagarde has echoed that call. One way to answer it is to rethink how commerce money itself is designed. That is where the closed loop comes in.

The simple definition

A closed-loop digital currency is a unit of value that can be spent only within a defined network of merchants and creators. It is not accepted everywhere, and it does not travel across the open card schemes. It works inside its own network, by design.

You already use closed loops. A transit card that only works on one city's network, a coffee chain balance that only buys coffee, and a gift card that only spends in one shop are all closed loops. The value is real, but where it can be spent is bounded. An open-loop instrument, by contrast, is a Visa or Mastercard card that spends anywhere the scheme is accepted.

What closed loop means, and what it does not

Closed loop describes how a currency is used. It is a product design choice, and a powerful one: it shapes cost, data and the experience of everyone in the network.

What closed loop does not do, on its own, is decide how a currency is treated in law. A prepaid unit of value that people buy with real money and spend with businesses other than the issuer is likely to be electronic money, and a network designed to keep growing is not a limited one. Any serious commerce currency should be built on that understanding from the start, with customer funds safeguarded and holders able to get their money back. KAELUM is designed on exactly that basis.

Why the loop matters

When value moves inside one governed network, three things become possible that the open card rails struggle to offer:

• Lower, clearer cost. Spending inside the network does not pass through card scheme interchange. One published platform fee applies instead, so merchants know exactly what a sale costs them.
• Real-time intelligence. Because every payment happens on one governed system, the network can understand demand, reward genuine commerce and spot fraud as it happens, rather than days later.
• Value that stays with participants. The savings from a shorter payment chain can be returned to the people in the network, as discounts for customers and loyalty for merchants, instead of leaking to intermediaries.

How KAELUM applies this

KAE is the KAELUM commerce currency. It is fixed at £0.20 per unit. Customers acquire KAE at that price, with no discount on purchase, and KAE never changes in value. It is not an investment, it is not traded and it is not cryptocurrency.

The benefit comes when KAE is spent. Customers receive a 6%+ discount on goods when they spend KAE with participating merchants and creators. A 4.5% platform fee applies. Merchants gain commerce intelligence and customer loyalty. Creators monetise their audiences through Social Paylinks and Commerce Drops. Rewards are tied to commerce, never to holding.

KAE is issued only when it is paid for at the fixed price, one unit for every £0.20. As KAELUM moves towards launch, it is designing for the protections that apply to electronic money: customer funds held in a safeguarded account by an authorised issuer, and the ability for holders to redeem their KAE at full value.

Governed by K.A.T.E.

Every KAE transaction is governed by K.A.T.E., the Ai engine powered exclusively by Claude, from Anthropic. K.A.T.E. governs the rails. You govern the spend. Users choose how much each capability can do for them, from simply observing to recommending, and sensitive actions always pass a human approval gate. An agent is never the thing that decides whether money moves: clear rules do, and when any check is unavailable, money waits for a person.

Where KAELUM stands today

The KAELUM platform and K.A.T.E. are built and in pre-launch testing. KAELUM is pre-launch and is working towards the appropriate regulatory permissions before it takes any customer funds.

The closed loop is not a shortcut around the rules. It is a better design for commerce money, built to sit inside them.

Crypto is powered by Blockchain. KAELUM is powered by Ai.

Learn more at kaelum.app.