Introducing ODON's Data Maturity Model (ODMM)

When working with Open Data across different domains, one challenge comes up repeatedly: what does it actually mean for data to be “open”? The answer depends on both legal permissions and technical usability — and the two don’t always go hand in hand.

To handle this consistently, regardless of domain or field, ODON developed the ODON Data Maturity Model (ODMM). The model assesses any dataset along two independent dimensions:

• Legal Openness — Can the data be legally used and reused? Levels range from L1 (closed or undefined, with no clear license) through L2 (restricted), L3 (open with conditions such as attribution), to L4 (fully open, with no legal barriers).
• Technical Openness — Can the data be practically accessed and used? Levels range from T1 (not usable, e.g. scanned PDFs) through T2 (accessible but limited), T3 (structured and standardised), to T4 (fully open and interoperable, with APIs and stable identifiers).

Each dataset receives a combined rating — for example, L3/T4 — giving a precise and actionable picture of how open a dataset really is.

The ODMM is already applied in ODON’s Data Catalog and guides how we evaluate and present datasets in our daily work. You can read the full model, including all levels and classification rules, on our Open Data page.