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Certification

Sales approval

The compliance check carried out before a public or private sale: due diligence, BIOP, provenance and authenticity verified before the hammer falls.

Updated : October 28, 2026· 4 min read

Pages in this section

Creamer, Louis Rorimer (c. 1910)ProcedureThe checks carried out, the documents to provide and the course of a sales approval request.› Sugar Bowl, Louis Rorimer (c. 1910)Auction housesThe role of auction houses in the certification chain, their obligations and the directory of approved houses.› Portrait Bust of a Man (27 BCE–14 CE)Private salesThe rules specific to private-treaty sales: named approval, confidentiality, transfer of ownership and reporting obligations.›

Selling with confidence

The Triumph of Mordecai, Lucas van Leyden (1515)
The Triumph of Mordecai, Lucas van Leyden (1515)

Sales approval is the green light given by OIMAP before a work is offered for sale. It checks that the lot is identified, that its seller is legitimate, that no alert applies to it and that its provenance is sufficient.

It protects the buyer, who acquires with confidence, and the seller, who avoids a dispute afterwards. It also protects the auction house, whose liability is engaged as soon as a disputed lot is sold.

Issued in 5 days for an indicative €540 excl. VAT, it is valid for one sale, public or private, within 90 days.

  • Due diligence
  • BIOP
  • Provenance
  • Sale

Approval in figures

5 daysturnaround
€540indicative price excl. VAT
90 daysvalidity
24referenced auction houses

Source: Certification Department, 2024.

Three pages to understand

Saucer with Scene in style of Watteau (c. 1750–60)StepsProcedure

Checks carried out and documents to provide to obtain approval.

›Twilight in the Wilderness, Frederic Edwin Church (1860)DirectoryAuction houses

The role of auction houses and the directory of approved houses.

›Teapot, Louis Rorimer (c. 1910)Private treatyPrivate sales

The rules specific to private-treaty sales.

›

What approval checks

Approval covers four points: the identity of the work (OIMAP number, passport), the seller's legitimacy (title of ownership or mandate), the absence of alerts (BIOP, appeals, restitution proceedings) and whether provenance is sufficient given the period and nature of the work.

For works more than one hundred years old, a provenance certificate is required; for archaeological or ethnographic objects, proof of lawful origin is added.

Seal Color Box (1662–1722)
Seal Color Box (1662–1722)
Side Drawer for Cabinet, André-Charles Boulle (c. 1690)
Side Drawer for Cabinet, André-Charles Boulle (c. 1690)
Beaker (c. late 600s–early 700s)
Beaker (c. late 600s–early 700s)

The four checks

Content of the compliance check
CheckWhat is verifiedDocument expected
IdentityThe work is registered and recognisableOIMAP number, work passport
SellerThe seller has the right to sellTitle of ownership or mandate
AlertsNo alert, no appealBIOP search
ProvenanceThe chain of ownership is sufficientProvenance certificate if necessary

From consignment to the hammer

  1. Consignment

    The seller entrusts the work to the auction house.

  2. Approval request

    The house submits the case at the Desk.

  3. Check

    Verification of the four points within 5 days.

  4. Approval

    The lot is declared compliant and published in the catalogue with the OIMAP mention.

  5. Adjudication

    The sale takes place; the transfer of ownership is declared in the Registry.

No approval, no OIMAP mention

Public sale or private sale

Mercury (Budha), from a Mandi Astrology Series, Sanju (c. 1810)

Public sale

Open auction
  • Public catalogue with OIMAP mention
  • Check of each lot
  • Approval valid for 90 days

The most common case.

Scenes of Daily Life, Roads and Paths: Road to Market (Scènes de la vie quotidienne, Routes et Chemins: Route du Marché), Carle Vernet (1819)

Private sale

Private treaty
  • Discreet sale
  • Identical check, confidential file
  • Named approval

See the dedicated page.

Approvals issued in 2024

Public sales73%
Private sales21%
Private-treaty sales in galleries6%

Source: Certification Department (indicative).

Typical timeline

  1. Consignment

    The lot is entrusted to the house.

  2. Submission

    Approval request at the Desk.

  3. Approval

    Lot declared compliant.

  4. Sale

    Adjudication.

  5. Transfer

    Declaration of the transfer in the Registry.

Boy with Anchor, Winslow Homer (1873)
Boy with Anchor, Winslow Homer (1873)
The Four Markets: The Fruit Market, Richard Earlom (1775)
The Four Markets: The Fruit Market, Richard Earlom (1775)
Chemin de fer de Toulouse à Bayonne. Pont de l'Aran (en trois arches de 17m d'ouverture chacune). Situation des travaux au 21 juillet 1861, Édouard Baldus (1861)
Chemin de fer de Toulouse à Bayonne. Pont de l'Aran (en trois arches de 17m d'ouverture chacune). Situation des travaux au 21 juillet 1861, Édouard Baldus (1861)

Case study: a problematic lot

An alert before the sale

Situation

An auction house prepares the catalogue for a spring sale.

Actions
  1. A lot of nineteen works is submitted for approval.
  2. The BIOP search reveals an alert on an engraving.
  3. The lot is withdrawn and the seller contacted.
Outcome

A disputed sale is avoided; the other eighteen lots are approved.

A point of ethics

The Market Place, Wells, Muirhead Bone (1891–1953)
« Due diligence is not an obstacle to selling: it is what allows you to sell without fearing the day after. »
Dr. Lucía Ferrer, member of the certification committee

Before consigning a lot

Vocabulary of the sale

Consignment
Deposit of a work with a professional with a view to sale.
Adjudication
Award of a lot to the highest bidder.
Due diligence
All the checks expected of a prudent seller or buyer.
Lot
Work or group of works sold under a single number.

Frequently asked questions

Is approval mandatory?

It is mandatory for houses holding the conformity label and recommended for all others.

Who requests it?

The auction house, or the seller themselves in a private sale.

What happens if an alert is discovered after approval?

Approval is suspended; the sale is postponed until the alert is lifted.

Does approval guarantee authenticity?

No: it attests that the sale is compliant. Authenticity falls under the certificate of authenticity.

Useful documents

Contacts

Eighteen Views of Rome: The Piazza Farnese (recto), Lievin Cruyl (1664)
Eighteen Views of Rome: The Piazza Farnese (recto), Lievin Cruyl (1664)
Certification DepartmentParis — Headquarters+33 1 00 00 00 00certification@oimap.exampleMonday to Friday, 9 a.m. – 5 p.m.

Request an approval

Corner Cabinet, René Dubois (c. 1765–1770)

Start with the procedure.

See the procedure
Image credits (22)
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