Attribution & licensing

Where the data comes from, what you may redistribute, and what we deliberately do not publish.

Nothing on this page is legal advice. It is a plain account of where each series comes from and what we believe you may do with it. You can make your own call, and a procurement reviewer can follow the chain without emailing us.

The chain

The public series today is Dutch imbalance prices, fetched from the ENTSO-E Transparency Platform. As Article 17 data it sits on ENTSO-E’s free re-use list under CC-BY 4.0. That listing makes it freely redistributable with attribution. We fetch it, store the raw payload immutably, and derive everything we serve from that stored copy. We never discard or rewrite a stored payload, so you can trace any value we publish back to the exact upstream document it came from.

What you may redistribute

Every series we hold carries a licence tag. We record the tag at ingest, from the terms we obtained the series under. The public API serves only series tagged as redistributable. That filter is fail-closed: the API refuses to serve a series with an unrecognised or missing tag, rather than serving it by default. If you can fetch it from api.tolven.eu without a key, it is data we believe you may use and pass on under the upstream terms, with attribution.

Attribute the upstream source, not us. For the imbalance series that means crediting the ENTSO-E Transparency Platform, as CC-BY 4.0 requires. We ask for no attribution of our own and claim no rights over the data itself — we did not create it. If you want to credit the cleaning and revision history as well, “via Tolven Energy Data” is welcome but never required.

What we deliberately do not publish

NL day-ahead prices. We do not serve them, and the reason is licensing rather than effort.

Dutch day-ahead prices are set on EPEX SPOT through Single Day-Ahead Coupling (SDAC). ENTSO-E does carry them, but that document is not on its CC-BY free re-use list: ENTSO-E’s terms make it free to access and not free to redistribute. We therefore cannot build anything public on it. The public API serves no day-ahead series, and the fail-closed licence filter above is what keeps it that way.

SMARD publishes day-ahead under CC-BY 4.0, but only for the German market areas: DE-LU, AT and LU. Its day-ahead API does not serve NL or the other neighbouring zones. The “neighbouring countries” panel on the SMARD website does display NL, but that is a front-end view rather than a downloadable CC-BY series.

That leaves the downstream republishers that appear to offer NL day-ahead under CC-BY. They assert that licence themselves, and we could not verify the chain behind it. One stamps its NL series as coming from SMARD while its own chart page credits ENTSO-E as the source. None, as far as we can verify, holds a right to sublicense the underlying EPEX/ENTSO-E data. The rights holders may tolerate that for public research; we could not rely on it commercially, so we do not build on it.

Publishing NL day-ahead properly means a distribution licence from the exchange, negotiated case by case rather than bought off a shelf. The line there is redistribution, not price. Handing the data to a third party is redistribution whether we charge for it or not, so no arrangement sidesteps it by giving the data away.

If you need NL day-ahead today, license it directly. If a German benchmark will do, SMARD publishes DE-LU day-ahead openly and you do not need us in the middle.

Until such a licence is in place, we declare the absence rather than fill it — the same principle we apply to gaps in the data. We would rather serve nothing than data we cannot defend.

Gaps and revisions are part of the record

Two things follow from taking provenance seriously:

We report gaps, never interpolate them. Where the upstream record has an interior gap, /v0/gaps/{dataset} will tell you so. We do not fill gaps with plausible numbers.

We keep revisions, never overwrite them. TenneT restates settlement, and we store each restated value as a new revision rather than replacing what came before. You can audit our history against the upstream publication timeline.

We treat a plausible number you cannot distinguish from a real one as worse than a gap.

Questions

If this page does not cover something you need for a procurement or compliance review, email the operator. The address reaches the engineer who runs Tolven, not a ticket queue.