A doubt is enough

An operator or private individual who comes across a work of murky origins has an essential role: they are often the first who can raise the alarm. Reporting a suspect work is confidential, protected and requires no proof.
A quarter of the records in the BIOP database come from such alerts. In 2024 they made it possible to block more than two hundred sales and to identify eleven resale networks.
This page describes the warning signs, the procedure and the protection of the reporter.
Reporting a suspect work in figures
Source: OIMAP Heritage Protection Department.
The warning signs
Several signs should alert you: a price far below the market, a seller in a hurry or evasive, a provenance that stops abruptly, incomplete or contradictory documents, transport requested with no supporting document, a payment in cash or by a third party with no apparent link.
Taken separately, none of these signs proves anything. It is their accumulation that justifies a report. If in doubt, do it: the analyst will judge, and a good-faith report exposes you to nothing.



How to report
Reporting is done online on the Desk, under the heading "Suspect work". The form asks for the description of the work, the place and date where it was seen, the possible identity of the seller, the nature of the suspicions and the documents you hold, such as a screenshot of the listing.
You may ask for anonymity: only the BIOP unit will know your identity, which it will pass to no one without your agreement, save a court obligation. No liability falls on a good-faith reporter.
What the BIOP unit does
An analyst examines the work, compares it with the database, checks the stated provenance and, if need be, contacts the national authorities. If there is no match, they may open a watch: the work is followed for several months and the reporter is informed if anything new occurs.
In case of a match or serious suspicion, the unit alerts the competent law enforcement. It never reveals to the seller the existence of a report: this rule protects the investigation and the reporter.
A civic role
Reporting a suspect work is not reserved to professionals. Many private individuals, students and visitors to salerooms have raised the alarm. Everyone can contribute to protecting heritage by staying alert and passing on what they observe.
Professional organisations now build this reflex into their training, with a clear message: a good-faith report is not an accusation, it is a service rendered to all.
Sign, risk and reaction
| Sign | Risk | Recommended reaction |
|---|---|---|
| Price far below market | Theft or fake | Ask for the provenance |
| Interrupted provenance | Looting or spoliation | Search in the BIOP |
| Evasive seller | Receiving | Refuse the transaction |
| Payment by a third party | Laundering | Report |
Landmarks
- Encounter with the work
Observation.
- Reporting
Confidential form.
- Analysis
BIOP unit.
- Decision
Watch, alert or closure.
Do not confront the seller



Report or simply refuse

Only refuse
Do not buy- Protects you
- Does not protect others
- The work can be sold elsewhere
Minimal reaction.

Report and refuse
Alert the unit- Also protects other buyers
- Helps the investigation
- No risk for the reporter
Recommended reaction.
Report a suspect work
- Observe
Note what you saw.
- Document
Capture listings and photos.
- Declare
Complete the form.
- Keep quiet
Do not alert the seller.
- Follow up
Answer requests.
Useful elements for the report
An auctioneer

« I reported a lot that looked dodgy to me. Three weeks later, the police thanked me: it was a piece stolen from a museum. »
Vocabulary of suspicion
- Receiving
- Holding property that comes from an offence.
- Monitoring
- Following a work without a public alert.
- Anonymity
- Non-publication of identity.
- Spoliation
- Unlawful dispossession of property.
Frequently asked questions
Am I liable if the suspicion is false?
No, every good-faith report is protected.
Can I remain anonymous?
Yes, the identity is known only to the unit.
How do I follow my report?
Through the Desk.
Where do I report in case of proven theft?
See Report a theft.
Useful documents
Contacts

See the active alerts
Image credits (16)
- Fish or Seal Club (X’ús’) (late 1800s–early 1900s) — Cleveland Museum of Art, CC0 1.0
- Nowshera, Kashmir (number 1000), Samuel Bourne (1864) — Cleveland Museum of Art, CC0 1.0
- Carnet (1863–1865) — Cleveland Museum of Art, CC0 1.0
- Gathering among the Members of Office Censor-General (1700s) — Cleveland Museum of Art, CC0 1.0
- Teapot with Landscape and Imperial Poem, Chen Hanwen (1762–95) — Cleveland Museum of Art, CC0 1.0
- La Belle Jardinère: le magasin de la rue de la Cité pendant sa demolition, Paris, Charles Marville (1864–66) — Cleveland Museum of Art, CC0 1.0
- Document Box (Ryōshibako) with Chrysanthemum and Plum (lid) (late 1800s-early 1900s) — Cleveland Museum of Art, CC0 1.0
- Lace Towel End (c. 1700s–1800s) — Cleveland Museum of Art, CC0 1.0
- Carved Lacquer Scroll Box (1736–95) — Cleveland Museum of Art, CC0 1.0
- Boy with Cigar (c. 1855) — Cleveland Museum of Art, CC0 1.0
- Seal with Two Qilin Playing (1849) — Cleveland Museum of Art, CC0 1.0
- Roman Ruins, Villa Pamfili, Hubert Robert (1774) — Cleveland Museum of Art, CC0 1.0
- 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) — Cleveland Museum of Art, CC0 1.0
- Seal of Doge Michele Steno (reverse) (1400–1409) — Cleveland Museum of Art, CC0 1.0
- Coin of Eukratides I (170–145 BCE) — Cleveland Museum of Art, CC0 1.0
- Bidri Hookah Bowl with Roses (c. 1650s) — Cleveland Museum of Art, CC0 1.0
Cleveland Museum of Art · CC0 1.0
Report a workDeclaring a theft, a loss or a suspect work: three procedures, a single aim, finding the work quickly.›
Active alertsThe 1,920 alerts currently in the BIOP database, sorted by country and type of property, and available as RSS feeds for operators and services.›
Reporting suspicious transactionsHow, when and to whom to report a suspicious transaction: procedure, content of the report, protection of the reporter and follow-up.›