OpenTwo archives, queried live.
Every record below comes from The Met or Smithsonian Open Access and was filtered on that archive’s own rights field before it reached this page. 12 shown for “6c Proprietary general issue revenue stamp plate proof” — 40 records examined, 0 dropped by the rights gate.
Archives queried 2026-08-31 23:18 UTC · fetched live for this request
isPublicDomain field is true for this object.metadata_usage.access reads CC0 — a waiver, not an expired term.The Metropolitan Museum of Art: HTTP 403 from collectionapi.metmuseum.org. Results from the remaining archive are shown unchanged — nothing is substituted for a source that did not answer.
6c Proprietary general issue revenue stamp plate proof
Artist not stated in the record · 1875-1883
6c Documentary Proprietary revenue stamp approved die proof
Artist not stated in the record · 1871
Boutwell presentation album
Artist not stated in the record · 1862-1874
6c General Douglas MacArthur plate proof
Bureau of Engraving and Printing · September 9, 1970
1c Proprietary revenue stamp trial color proof
Joseph R. Carpenter, American · 1871
1c Documentary Proprietary revenue stamp with fancy cancel single
Artist not stated in the record · 1862
6c Franklin D. Roosevelt plate proof
Bureau of Engraving and Printing
6c Transport Plane plate proof
Bureau of Engraving and Printing
6c Transport Plane plate proof
Bureau of Engraving and Printing
6c Franklin D. Roosevelt plate proof
Bureau of Engraving and Printing · December 28, 1967
6c Grandma Moses plate proof
Bureau of Engraving and Printing
6c Theodore Roosevelt plate proof
Bureau of Engraving and Printing · October 6, 1955
Where these records came from.
Two archives are wired, and only two. Each one is filtered on its own rights field — never on a title match, and never on the presence of an image file.
- The Met Collection API (Open Access)Rights field:
isPublicDomain. HTTP 403 from collectionapi.metmuseum.org. No records from this archive are shown for this query.Unavailable - Smithsonian Open Access API (api.si.edu)Rights field:
content.descriptiveNonRepeating.metadata_usage.access. 413329 matched · 40 examined · 0 dropped by the rights gate. Kept only where metadata_usage.access === "CC0" and an image resource was published.12 shown
These figures describe the pass run at 2026-08-31 23:18 UTC, during this request. A completed pass is kept for 24 hours and replayed for an identical search, which is what keeps repeated queries inside Smithsonian’s 30-requests-per-hour allowance. A pass in which either archive failed to answer is never kept — an outage must not be replayed as though it were a finding about the catalogue.
Wikimedia Commons and the Library of Congress are deliberately not wired. Wikimedia was confirmed, on a live query, to return CC-BY material inside the same result set as genuine public domain works, and filtering it safely has not been designed yet. loc.gov was blocked by bot detection during the source evaluation, so its rights vocabulary has never been observed — and nothing here is built on a field nobody has read.
An image file is a rights claim. It never travels without its field.