Article I
Certificates of provenance
No piece shall leave the house without a true account of its making, signed by its makers. The account is the certificate. The house has written one for everything it has made since the Copyist, and has kept a copy of each.
What a certificate records
A Rosen certificate is a single folded sheet of cotton paper, written in iron gall ink, that records what a piece is, when and where it was made, what it is made of, the hallmarks struck on it and, in the order in which they worked, the name and trade of every person who worked on it. It is signed by the maker of record, the Master of the Atelier and the Registrar, in that order, and entered in the Register of Provenance on the day the piece leaves the House.
When a piece is serviced or overhauled, the work is added to the certificate with the names of the makers who did it. When a piece changes hands, the change is noted in the Register, though not on the certificate, which belongs to the piece and not to its keeper.
The Register
The Register of Provenance has been kept without a break since the morning of 14 March 1911, when its first entry recorded the Register itself. It runs to forty-three bound volumes and, since 1998, a second, digital copy that the Registrar checks against the bound volumes every night. Article VII forbids the Register to be closed while the house stands.
Penfield instruments carry certificates in their own series: P 1 to P 61 412 for the Mk IV, in a separate volume. Nexus-6 certificates, Nos. 120 001 to 122 318, are held by the Recall Office for the duration of the recall.
Why the house bothers
Because a convincing object without a history is a forgery, however honestly it was made, and the house makes convincing objects. The certificate is how a keeper, a buyer, a museum or a court can know that a Rosen piece is what it says it is, without having to trust how it looks. It is also, in the house’s view, a courtesy to the makers, who are owed their names.
The test is not how well a thing is made but whether anyone is told.
Specimen
A Penfield certificate
The certificate of a Penfield Mk IV, transcribed, with the keeper’s details omitted as they are omitted from every public copy.
Penfield Mk IV, bedside instrument
Certificate of provenance No. P 30 117 · Penfield volume, fol. 1,207
- Made
- The Penfield Works, Everett. Left the Works 11 March 2025
- Case
- Walnut, French-polished
- Dial
- Engraved brass, forty-eight registers, from the master of 2022
- Hallmarks
- House mark; year letter e, for 2025; the Penfield Works; the maker’s mark
- Firmware
- 4.1.0 at leaving; 4.2.1 since 4 July 2026
- Servicing
- None yet recorded. First overhaul due March 2032
Hands, in the order in which they worked
- Hannah Voss, case
- Luis Carrillo, turning
- Wendy Achterhof, dial, engraved from the master by Tobiah Wren
- Grace Pemberton, detent and drum
- Samir Aziz, contact band
- Joel Martinsen, assembly
- Odile Brisbois, regulation
- Marit Solberg, tuning
J. MartinsenMaker of record
O. BrandvoldMaster of the Atelier
D. AchterbergRegistrar
Lost or disputed certificates
If a certificate is lost or damaged, the Registrar will issue a certified copy from the Register, marked as a copy, to the registered keeper. If you are offered a piece described as Rosen work without a certificate, or with a certificate that does not match the Register, please write to the Provenance Office before you buy it. The house will tell you what it knows, and it will not tell you what it does not.
Verify a certificate by its number · Heritage extracts from the Archive