OpenRTB field was removed in this version
The field was removed in the selected version and is no longer valid.
What it means
The field was part of an earlier OpenRTB release but was removed by the version you validated against, so it is no longer defined at this path.
Why it matters
Consumers on this version do not read the field, and a strict parser may reject the containing object. Payloads carrying removed fields usually indicate a builder pinned to an old spec revision, which tends to come with other stale paths as well.
How to fix it
Remove the field, or move to the replacement the finding names if one exists. If you must keep serving an old integration, send it a payload targeted at the version it actually speaks rather than mixing eras in one document.
Example that trips it
rtblint validate --version 2.6-202606 request.json
{ "imp": [{ "id": "1", "banner": { "w": 300, "h": 250, "wmax": 728 } }] }banner.wmax was deprecated before 2.6 and deleted in it. Against 2.5 the same payload reports the softer openrtb.field.deprecated, so the version you validate against decides which of the two you see.
Check your payload
Paste a bid request or response into the tester to see whether this code fires against it, or gate on the id in CI with the CLI: the id is stable, wording is not.
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