The UK Competition and Markets Authority's Retail Banking Market Investigation Order 2017 is the competition remedy that created UK Open Banking. It required the nine largest UK banks (the CMA9) to adopt and maintain a common, open API standard and funded the Open Banking Implementation Entity (OBIE) to write the specification, run conformance, and operate a directory — the delivery machinery that made the UK the reference open-banking regime.
CMA Open Banking Order
The UK’s Retail Banking Market Investigation Order 2017 is the piece most people forget when they credit the UK’s open-banking success to PSD2. Open banking in Britain was not only a payments directive — it was a competition remedy. The Competition and Markets Authority, having found that entrenched incumbents made it too hard for customers to switch and for challengers to compete, ordered the nine largest banks to open up.
- It named the CMA9 - The Order applied to the nine largest UK current-account providers and required them to adopt and maintain a single, common, open API standard rather than nine incompatible ones.
- It created a delivery body - The Order established and funded the Open Banking Implementation Entity (OBIE) to write the specification, run a conformance regime, and operate a trust directory — the machinery a bare mandate lacks.
- Antitrust through interoperability - This is mandated interoperability as a competition tool: prying open a concentrated, data-hoarding market by requiring standardized access, redistributing power toward consumers and challengers.
The CMA Order is why the UK is the model everyone copies. A mandate that names its targets, funds a delivery body, and enforces conformance reaches past existence to usefulness — the distinction at the heart of every open-banking regime I score.
Referenced in API Evangelist papers
This regulation shows up in my published research. These reports read the machine-readable evidence provider by provider — and put this regulation in the context of a real sector.
The State of UK Banking APIs
The competition remedy that named the CMA9 and funded OBIE — the reason the UK mandate reached past existence to usefulness.
Implemented by these standards
A regulation is the law; a standard is the machine-readable contract that makes it real. These are the technical standards that implement this regulation, catalogued at contracts.apievangelist.com.
UK Open Banking Standard
OBIE wrote and maintains this standard under the CMA Order.
