Achieves "Diamond-level" Open API Certification

Cerillion PLC

26 March 2026

 

AIM: CER

Cerillion plc

("Cerillion" or "the Company")

Achieves TM Forum "Diamond-level" Open API Certification

with Industry-leading 'Real-world' Deployments

Cerillion, the billing, charging and customer relationship management software solutions provider is pleased to announce that it has achieved "Diamond-level" status in TM Forum's Open API Conformance programme, which recognises vendors that have certified more than 50 Open APIs.

Cerillion has 32 Real World Open API certifications across five live customer deployments. This means that the Company has the highest number of TM Forum Real World Open API certifications of any BSS/OSS vendor. Real-world certifications validate APIs that are proven in operational environments, rather than tested solely in lab conditions.

While a small number of BSS/OSS vendors have reached Diamond status, Cerillion leads the market in both the quantity and breadth of its real-world implementations across multiple customer environments, demonstrating a repeatable delivery model that reduces risk and delivers predictable, real-world results.

TM Forum Open APIs are a critical foundation for composable, interoperable BSS/OSS architectures. However, product certification alone does not guarantee successful implementation.

Cerillion's approach is differentiated by its API-first architecture, where Open APIs are embedded natively within its BSS/OSS Suite and underpin all system functionality - from user interfaces and workflows to integration and extensibility. This ensures that the same APIs used for certification are those driving live operations, enabling consistent delivery, seamless interoperability, and integration with emerging standards such as the Model Context Protocol (MCP).

Louis Hall, CEO of Cerillion plc, commented:

"Diamond-level status is an important milestone, but the real story is how those certifications have been achieved. Our API-first approach ensures that TM Forum Open APIs are built into the core of our solution. The result is not just compliance, but proven delivery in live customer deployments - giving our customers real confidence and certainty of outcome."

Enquiries:

Cerillion plc Louis Hall, CEO		c/o KTZ Communications T : 020 3178 6378
KTZ Communications		T: 020 3178 6378
Katie Tzouliadis, Robert Morton

About Cerillion

www.cerillion.com

Cerillion has a 26-year track record in providing mission-critical software for billing, charging and customer relationship management ("CRM"), mainly to the telecommunications sector but also to other markets, including utilities and financial services. The Company has c. 70 customer installations across c. 45 countries. Headquartered in London, Cerillion also has operations in India and Bulgaria as well as a sales presence in Continental Europe, the USA, Singapore and Australia.

The business was originally part of Logica plc before its management buyout, led by CEO, Louis Hall, in 1999. The Company joined AIM in March 2016.

 

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