How to tell whether an artwork is stolen before you buy it

Verified on 29 October 2026. Should any information have changed, please notify me and I shall update it with the date of the revision.

An invoice, a certificate of authenticity or the seller’s reputation are not enough to show that a work belongs to the person offering it for sale. No single check guarantees that its origin is lawful, but several consistent checks, carried out before payment and properly documented, reduce the risk and make it possible to show the diligence exercised.

This guide focuses on a purchase made in Spain: how to identify the work and the seller, reconstruct its provenance, search registers of stolen objects, document the transaction and act if warning signs appear. It does not replace legal advice on a specific case.

If the work has already gone missing, see What to do if an artwork is stolen. To review as well its physical condition, authenticity and the general terms of acquisition, start with Before buying a work: provenance, condition and documentation.

Good faith does not settle the dispute on its own

Article 464 of the Civil Code establishes that possession of movable property acquired in good faith is equivalent to title, but adds that anyone who has lost a movable object or has been unlawfully deprived of it may claim it from whoever holds it. The article also contains specific rules for goods acquired in good faith at a public sale, those pledged at pawnbrokers (Montes de Piedad), and those bought on a stock exchange, at a fair or market, or from a lawfully established dealer who habitually trades in similar objects.

In the latter case, Article 464 refers to the Commercial Code. Its Article 85 provides that the purchase of goods in warehouses or shops open to the public causes the right to be acquired by prescription in favour of the buyer, without prejudice to the civil or criminal actions the owner may bring against whoever sold the goods improperly. Articles 1955 and 1956 of the Civil Code also contain rules on the acquisitive prescription of movable property and on stolen movable objects.

These rules do not allow a claim to be resolved by looking only at the invoice or at the good faith the buyer invokes. What matters is how the work was acquired, who the parties are, the nature of the establishment, the buyer’s conduct before purchasing and the evidence available. If someone claims a work that you already hold, you need individual legal advice.

Due diligence also has express effects on the restitution of certain cultural goods that have unlawfully left another Member State of the European Union. Act 1/2017 provides for fair compensation for a possessor who shows that they acted with due diligence and requires the assessment of, among other circumstances, the provenance documentation, export authorisations, the status of the parties, the price paid, the consultation of accessible registers of stolen cultural goods and the other steps a reasonable person would have taken.

The 1995 UNIDROIT Convention uses similar criteria as an international reference: the character of the parties, the price, the documentation available, the consultation of reasonably accessible registers, and other prudent actions. The practical utility of these criteria does not mean that the Convention is applicable to any purchase made in Spain; its application depends on the States bound, the international nature of the claim, and its temporal rules.

Due diligence must be provable. Keep not only the result of a search but also its date, the data entered and the documents examined.

What to check before paying

Identify the work

Gather clear photographs of the obverse, the reverse, the signature, labels, stamps, the frame and any distinctive marks. Record the attributed authorship, the title, the date, the technique, the medium, the dimensions and, if it is an edition, its numbering. Compare these data with the documentation and require that the invoice or contract identify the piece without ambiguity.

A certificate of authenticity may give information about authorship, but it does not prove by itself that the seller is the owner or that the work has circulated lawfully. How to prepare a certificate of authenticity for an artwork explains what it must contain and what its limits are.

Identify the vendor and their right to sell

Request the full name or company name, the tax identification number (NIF), the address and verifiable contact details. Determine whether they are acting as owner, gallery, auction house, intermediary, representative or heir.

Request the document that explains how they obtained the work and why they are entitled to sell it: invoice, sale contract, award, deposit agreement or mandate to sell. If it comes from an inheritance, the documents must make it possible to verify the succession and the power of disposal. Where an intermediary is involved, ask them to identify the owner and prove their authority. If they invoke confidentiality, that reservation must not prevent a sufficient check of title and provenance.

Reconstruct the provenance

Ask who held the work, for what period and through what transaction it passed to the next owner. Check each link against invoices, contracts, inventories, catalogues, insurance policies, dated photographs, correspondence or other documents. A verbal account may guide the investigation, but it does not replace evidence.

Pay special attention to:

Prolonged gaps without a known owner.
Dates, dimensions, titles or descriptions that are incompatible with one another.
Documents that do not allow the specific work to be identified.
Alterations, erasures, incomplete copies or files without a verifiable origin.
European provenance between 1933 and 1945 that is not sufficiently explained.
An abnormally low price relative to the context of the sale.
Pressure to pay immediately or outside of customary channels.
Refusal to issue an invoice, identify the owner or explain the provenance.

Do not fill in gaps with assumptions. The absence of documentation does not by itself demonstrate a theft, but it increases uncertainty and may justify suspending the purchase. The general method is set out in Provenance of a work of art: what it is and why it decides its fate.

Search registers of stolen works

INTERPOL. Its database holds descriptions and images of more than 57,000 stolen or missing objects, with certified police information. Records can only be supplied by authorised entities and must refer to clearly identifiable objects. Anyone may apply for access as an authorised user. The ID-Art app allows searches by descriptive data or by image.

Keep a record of each search. ID-Art lets you save manual searches with the date and time, and INTERPOL notes that these timestamps can help to show which checks were carried out. If you use the visual search, also keep a screenshot, the image used and the date. Repeat the search shortly before paying if time has passed since the first check.

Art Loss Register. This is a private database of lost or stolen works, antiques and collectables. It is not open to the public: the service carries out a search using the information you supply. Before engaging it, check in writing its scope, cost, turnaround time and what the result will contain.

Specialised registers. If the provenance so requires, also consult the databases of the relevant country. The Carabinieri Command for the Protection of Cultural Heritage maintains the iTPC database. The German Lost Art database is especially relevant for cultural property displaced or confiscated through Nazi persecution and for losses linked to the Second World War; it does not replace a general search for stolen objects.

That a work does not appear in a database does not show that its origin is lawful. The theft may not have been reported, the object may not be described in enough detail, or the record may not yet have been added. A negative search is a useful check, not a certificate of lawful origin.

Tailor the review to the purchase channel

Gallery or dealer. Verify the professional's identity, the description of the work, the declared provenance, and the terms for returns or claims. Act 10/2010 treats as obliged entities those who trade professionally in works of art or antiques or act as intermediaries in that trade. This explains why they may request identity documentation and details regarding the transaction; that does not make their involvement a guarantee of title. The reason for this request is explained in Why a gallery may ask for your ID when you buy a work.

Auction house. Read the terms applicable to that specific sale, rather than general conditions from another venue or format. Review the house's declarations regarding ownership, provenance, catalogue attributions, lot withdrawals, and claims. A public sale may influence the civil treatment of a potential claim, meaning a high-value piece or one with incomplete provenance requires professional advice before bidding. Conditions, premiums and collection are covered in Buying art at auction: estimate, premium, condition and collection.

Inheritance. Verify that the work forms part of the estate and that the person selling it is entitled to dispose of it. If there are several heirs or the allocation is unclear, do not assume that one of them can transfer it alone. Receiving a work by inheritance does not cure an earlier unlawful provenance.

Intermediary or online sale. Identify the actual owner and the physical location of the work. Do not make payment based solely on photographs, a provenance narrative, or a digital profile. Cross-border transactions introduce issues of jurisdiction, export, customs, and returns that must be resolved prior to payment.

Work originating from another country. Verify export authorisations and customs documentation. For certain cultural goods originating from countries outside the European Union, Regulation (EU) 2019/880 may apply. The legality of the export in the country of origin and the legality of the import into the Union are checks distinct from authenticity and ownership. The entry of these goods into the Union is explained in Importing cultural goods into the EU: licences and importer declarations.

Document the transaction

Keep in a single file:

The invoice and the contract, with sufficient identification of the work and the seller.
The photographs and the record sheet of the work.
The documentation of provenance and ownership.
The certificate of authenticity, if available.
Export or import authorisations, where applicable.
Searches in registers, including date, criteria, and results.
Relevant correspondence and messages.
The accepted terms of sale.
Proof of payment.

When either party acts as a business or professional, Act 7/2012 prohibits cash payments for transactions of 1,000 euros or more. The limit rises to 10,000 euros when the payer is an individual with no tax residence in Spain who is not acting as a business or professional. Splitting the payment does not avoid the limit. Even outside these cases, a traceable means of payment makes the transaction easier to prove.

Reflect guarantees in writing

The contract or invoice should include, depending on the importance of the transaction:

The description of the work and photographs that allow for its identification.
The identity and address of the seller.
A declaration that the seller is the owner or is authorised to sell.
A declaration that the work is transferred free of any known encumbrances or claims.
The declared provenance and the documentation provided.
A commitment to cooperate in the event of a well-founded claim.
The consequences of a lack of ownership or restitution to a third party.
The method of payment and the applicable law in international transactions.

These clauses must be adapted to the transaction. They do not replace prior investigation and offer little protection if the seller cannot be located or lacks solvency.

The Civil Code regulates the seller’s warranty against eviction in Articles 1475 to 1483. In general, the seller is liable when the buyer is deprived, by final judgment, of all or part of what was acquired by virtue of a right prior to the purchase. The regulation contains requirements and limits, including the need to notify the seller of the eviction claim. If a claim arises, do not negotiate or let deadlines pass without professional advice.

When to suspend the purchase

Do not make payment or accept delivery while the situation remains unclear if:

The seller does not prove their identity or their authority to sell.
The description of the work does not match the documentation.
There are significant contradictions in the provenance.
The work matches or presents significant similarities to an object registered as stolen.
The price, urgency, or method of payment lacks a reasonable explanation.
An invoice, a contract or a traceable payment is refused.
Required export or import permits are missing.
The documentation shows signs of alteration or cannot be verified.

A match in a database must be reported through the channel the register itself indicates and to the competent authorities. In Spain, the Guardia Civil has the Historical Heritage Group of the Central Operational Unit (UCO) and territorial Judicial Police units. If your suspicion is well founded, use the official channels currently in force and do not warn or confront the seller if that could compromise the investigation or the preservation of the work.

If indications appear after purchase

Do not sell, conceal, alter, or move the work unless instructed by the authority or the professional handling the case.
Keep the work in secure conditions and document its state.
Retain the advertisement, invoice, contract, proof of payment, communications, and searches conducted.
Note which indication appeared, when, and why it is relevant.
Consult immediately with a lawyer experienced in art law or cultural heritage.
Communicate a match or well-founded suspicion to the authorities via their official channels.
Notify the seller in the manner and at the time advised by the professional directing the claim.

Receiving stolen goods under Article 298 of the Criminal Code requires, among other elements, a profit motive and knowledge that the items come from an offence against property or the socio-economic order. Article 301 regulates money-laundering conduct involving goods of criminal origin and includes a form of the offence committed through gross negligence. The existence of a warning sign does not by itself allow the conclusion that an offence has been committed, but ignoring relevant indications or continuing to transfer the work may aggravate the problem. The criminal assessment depends on the facts and must be made by a professional.

If unlawful provenance is confirmed, see Restitution and responsible acquisition: what to do when provenance is problematic.

Checklist

☐ I have identified the work using photographs, measurements, inscriptions, and distinctive features.
☐ I have verified the seller's identity and their right to sell.
☐ I have reconstructed the provenance and recorded its gaps or contradictions.
☐ I have consulted the INTERPOL database and retained dated proof.
☐ I have reviewed other registers where provenance advised doing so.
☐ I have repeated the searches if time elapsed before payment.
☐ I have reviewed the specific conditions if purchasing at auction or online.
☐ I have checked export and import permits where applicable.
☐ The invoice and contract identify the work and the seller.
☐ The contract includes the essential declarations and consequences.
☐ Payment is made via a legal and traceable method.
☐ I am keeping all documentation in a single file.
☐ I know which warning signs mean I should suspend the purchase.

Matters requiring individual advice

Consult a professional before concluding the transaction when dealing with a high-value work, incomplete provenance, a public sale, a prior claim, an inheritance not yet allocated, an export or import, a match in a register, or doubts about title. Also consult a professional when you need to determine the applicable law, draft specific warranties or respond to a claim.

Itineraries

I am building or managing an art collection

Incorporate these checks into a stable acquisition protocol. Open a file for each work before payment and keep with it the photographs, seller documentation, dated searches, contract, invoice, and proof of payment. A well-documented collection is better protected against theft, claims, and future transfer.

An open conversation

This guide gathers regulations, guidance from authorities, and practical recommendations. Registers, contact channels, and the conditions of private services change. If you work in heritage, a gallery, an auction house, conservation, or art law and detect an error or a scenario that requires clarification, you may write to me.

Sources

Regulations

Civil Code, arts. 464, 1475 to 1483, 1955 and 1956.
Commercial Code, art. 85.
Criminal Code, arts. 298 and 301.
Act 10/2010, on the prevention of money laundering and the financing of terrorism, art. 2.1.r).
Act 7/2012, amending tax and budgetary regulations, art. 7.
Directive 2014/60/EU, on the return of cultural objects.
Act 1/2017, on the return of cultural objects.
Regulation (EU) 2019/880, on the introduction and import of cultural goods.
1995 UNIDROIT Convention on Stolen or Illegally Exported Cultural Objects, art. 4.4.