Translated from the French original.
I. Introduction
Seated Man (Leaning on a Cane), painted by Amedeo Modigliani in 1918, is at the centre of one of the most prominent restitution disputes of recent years. The work was looted during the German occupation of France after its owner, the Jewish art dealer Oscar Stettiner, fled. It resurfaced at a Christie’s sale in 1996 and was acquired by a company controlled by David Nahmad.
After years of litigation, the New York State Supreme Court ordered the painting’s return to the Stettiner heirs on 3 April 2026, finding that it had been looted during the Second World War. In June 2026, David Nahmad was given thirty days to surrender the work. The art dealer’s lawyers promptly announced their intention to challenge the decision. At the time of writing, the proceedings therefore appear to be ongoing.
This article examines that decision and the historical and legal context in which it was made. It also considers Switzerland’s position during that period and how Swiss law treats good-faith acquisitions of artworks during or after the Second World War. The case offers an opportunity to examine the tensions between the security of transactions, the protection of good faith and the need to remedy historical injustices.
II. Facts
Before the Second World War, Oscar Stettiner, a British art dealer of Jewish origin, lived in Paris. He was a shareholder in Stettiner & Cie, based at 18 avenue Matignon. The company dealt primarily in antiques and was occasionally active in the modern art market.
Seated Man (Leaning on a Cane) first appears in the records of the 1930 Venice Biennale as belonging to Oscar Stettiner.
Forced to flee Paris in 1939, Stettiner left his gallery behind. His property was placed under provisional administration and subsequently dispersed by the Commissariat-General for Jewish Affairs. On 3 July 1944, Seated Man (Leaning on a Cane) was sold to the American dealer John Van der Klip for 16,000 francs.
After the liberation of France, Stettiner brought proceedings before the French courts. In a 1946 judgment, the Civil Court of the Seine recognised his ownership of the painting, characterised the 1944 sale as an act of looting and ordered its return. The order also provided for a penalty payment of 300 francs per day in the event of non-compliance. A bailiff was instructed to enforce the decision in March 1947.
Although Van der Klip acknowledged that he had bought the Modigliani at the 1944 sale, he claimed to have entrusted it to a man named Mariage de Saint-Pierre. The latter, in turn, stated that he had resold it in October 1944 to an American officer whom he had met in a Paris café and whose name and address he did not know.
The painting resurfaced at a Christie’s sale in 1996, where it was purchased for USD 3.2 million by the Panamanian company International Art Center (IAC). The Panama Papers later revealed that IAC was controlled by the art dealer David Nahmad. Long kept in the Geneva freeports, the work was subsequently valued at approximately USD 25 million.
In 2011, Oscar Stettiner’s grandson, Philippe Maestracci, began proceedings before the US courts to recover the painting.
III. Decision of the New York State Supreme Court
In its decision of 3 April 2026, the New York State Supreme Court first referred to the US Holocaust Expropriated Art Recovery Act of 2016 (HEAR Act), which aims to ensure that claims for the return of art looted during the Nazi era are considered fairly and are not dismissed solely because of the passage of time. The Court then examined the claims for conversion and replevin.
Conversion occurs when a person intentionally exercises unauthorised control over personal property belonging to another, thereby interfering with that person’s right to possession (Colavito v. New York Organ Donor Network, Inc., 8 NY3d 43, 49–50 [2006]). It therefore requires two elements: first, that the claimant have ownership or a possessory interest in the property; and second, that the defendant exercise control over or interfere with it in violation of the claimant’s rights (Reif v. Nagy, 175 AD3d 107, 120 [1st Dept 2019]).
In this case, the Court found that the claimant had established that Stettiner owned the painting or, at the very least, had a superior right to possess it before it was looted, and that he had never voluntarily relinquished it. The Court relied on a body of consistent evidence, including records from the 1930 Venice Biennale, shipping documents, the original label on the back of the painting and several documents dating from the Occupation. These showed that Stettiner had lent the work to the Biennale and was identified there as its owner.
The Court also found that the painting was among the property dispersed at the sale held at the Hôtel Drouot in July 1944, even though it was not expressly listed in the catalogue. In establishing Stettiner’s ownership, the Court attached particular weight to the 1946 French decision, which had already recognised his title and characterised the 1944 sale as an act of looting. That decision also established that the sale was involuntary and that Stettiner had not abandoned his rights.
The Court rejected Van der Klip’s account that he had resold the work to an unidentified American officer, given that the painting ultimately resurfaced in the possession of his descendants when it was sold at Christie’s in 1996.
The Court further observed that the provenance set out in Christie’s 1996 catalogue was substantially inaccurate or misleading. The defendants acknowledged that they had relied entirely on that information without conducting any independent provenance research.
The arguments advanced to challenge Stettiner’s rights were dismissed as largely speculative. Neither the absence of an invoice or proof of purchase, nor the suggestion that Stettiner & Cie rather than Stettiner personally had owned the painting, nor the uncertainties concerning the identification or authenticity of the work sold in 1944 were sufficient to raise a genuine issue of fact. The defendants had argued, in particular, that the low sale price of 16,000 francs showed that the work could not have been a Modigliani.
Finally, the Court rejected the defence of laches. That defence requires the possessor to show that the delay in bringing proceedings caused prejudice; the passage of time alone is insufficient (In re Peters, 34 AD3d 29, 37 [2006]; Reif v. Nagy, 175 AD3d 107, 130 [2019]). No such prejudice was established here. The Court instead found that Stettiner had taken the steps reasonably available to him to locate the painting, and that his search had been hampered by its concealment and Van der Klip’s false statements.
IV. Context and Possible Outcome under Swiss Law
The New York State Supreme Court’s decision raises the question of how a similar dispute might have been resolved in Switzerland. This is of particular interest because the painting remained in the Geneva freeports for many years and Swiss law has traditionally protected good-faith purchasers.
The historical context must first be recalled. The looting of artworks under the Nazi regime formed part of a systematic policy of persecution whose consequences continue to give rise to particularly complex disputes.
The National Socialist period (1933–1945), which began with Adolf Hitler’s rise to power, was marked by an antisemitic policy aimed at promoting the supposed superiority of the “Aryan race” and persecuting populations deemed “inferior”, particularly Jews (Gérard Jacoby, Les lois de Nuremberg et la situation légale des Juifs en Allemagne, in: Europe, vol. 40, no. 159, 1936, pp. 417 and 47). Between 1939 and 1944, the Nazis systematically confiscated numerous public and private collections across Europe.
Switzerland’s situation was different because it did not directly participate in the Second World War. Unlike France, it was not occupied by Hitler’s armies (Marc Perrenoud, Les spoliations, la Suisse et les suisses (1933–1946), in: Revue d’histoire de la Shoah 2017, no. 186, p. 411 (“Perrenoud”)). Nevertheless, its art market, financial institutions and geographical position facilitated certain transactions and made the country an important transit point for such works (Perrenoud, pp. 411 et seq.).
To address this situation, Switzerland adopted measures shortly after the Second World War to facilitate the return of cultural property looted under the National Socialist regime (Marc-André Renold/Pierre Gabus, Claims for the Restitution of Looted Art, Schulthess, Geneva/Zurich 2004, p. 12 (“Renold/Gabus”)). It adopted the Federal Council Decree of 10 December 1945 concerning actions to recover property removed from occupied territories during the war. The decree set aside the rules protecting good-faith purchasers and governing acquisitive prescription where the owner showed that the property had been looted in occupied territory in breach of public international law (Renold/Gabus, pp. 12–13; Perrenoud, p. 411).
The owner could thus recover the property, while a good-faith purchaser had a claim against the seller or, failing that, a right to compensation from the Confederation (Renold/Gabus, p. 13).
This exceptional regime was, however, limited in time: restitution claims had to be filed by 31 December 1947 (Renold/Gabus, p. 12). Outside that special regime, the ordinary rules of the Swiss Civil Code apply and may prevent the return of looted cultural property.
Article 728(1) of the Swiss Civil Code provides that a good-faith possessor acquires ownership of movable property after five years of uninterrupted possession. Acquisitive prescription therefore remains dependent on good faith, which is presumed under Article 3 of the Swiss Civil Code and, in principle, need not be proved (ATF 50 II 338).
(i) Case law
Swiss case law illustrates the decisive role of good faith in disputes concerning looted artworks. The case of The Stour Valley provides an example: although the painting’s looted origins had been established, acquisitive prescription prevented its recovery because the City of La Chaux-de-Fonds was considered a good-faith possessor.
The painting was acquired in 1946 by Mr and Mrs Junod from Galerie Moos in Geneva. On 28 April 1986, the General Council of La Chaux-de-Fonds, in the Canton of Neuchâtel, accepted a bequest from Madeleine Junod that included John Constable’s The Stour Valley. The work thus entered the collection of the Musée des Beaux-Arts de La Chaux-de-Fonds.
In 2006, Anna Jaffé’s heirs sought its return, arguing that the painting had been looted by the Nazis before being sold at auction in Nice in 1943.
Although the painting’s looted origins were not disputed, the outcome of any restitution claim depended chiefly on whether the City of La Chaux-de-Fonds could be shown to have acted in bad faith. According to a legal opinion by Professor Lalive, there was no evidence that Madeleine Junod or the Museum knew, or should have known, of the painting’s looted origins within the meaning of Article 3 of the Swiss Civil Code. Since the City had possessed the work peacefully and without interruption from 1986 until 14 June 2006, it had acquired ownership by prescription under Article 728(1) of the Swiss Civil Code. Any bad faith on the part of earlier holders, including Galerie Moos or the Junods, had no bearing on that acquisition.
A voluntary return also encountered an obstacle in the conditions attached to the bequest under Article 482 of the Swiss Civil Code. Madeleine Junod had required the City to keep the painting at the Musée des Beaux-Arts de La Chaux-de-Fonds, display it as part of the René and Madeleine Junod Collection, and refrain from disposing of it. Returning the work would therefore have breached the obligations arising from the bequest and could have prompted an action for enforcement by the Junod heirs or other interested parties.
In 2017, giving overriding weight to ethical considerations, the City decided to return the painting to the heirs. This became possible after Madeleine Junod’s heirs agreed to lift the condition prohibiting its disposal.
By contrast, in Cassirer v. Thyssen-Bornemisza Collection Foundation, the US courts found that an experienced collector could not rely on good faith where the circumstances called for further research into the painting’s provenance.
In 1900, Paul Cassirer acquired Camille Pissarro’s Rue Saint-Honoré, Afternoon, Rain Effect. The work passed to Lily Cassirer Neubauer in 1926. In 1939, she was forced to surrender it in exchange for a visa that enabled her to flee Nazi Germany. Decades later, her heirs discovered that the painting was held by the Thyssen-Bornemisza Collection Foundation and brought restitution proceedings before the US courts.
The painting had been acquired by Baron Hans Heinrich Thyssen-Bornemisza, who first lent it to the Spanish State before selling the majority of his collection to the Kingdom of Spain. The foundation bearing his name was then established to preserve and manage the collection. The dispute presented a particular choice-of-law issue: although the US courts heard the case, the validity of the successive acquisitions had to be assessed first under Swiss law, in relation to the Baron’s acquisition, and then under Spanish law, in relation to the Foundation’s acquisition.
Whether the Baron had acquired ownership of the painting by prescription had to be assessed under Swiss law because the work had been kept in his collection in Switzerland between 1976 and 1992. Under Article 728 of the Swiss Civil Code, acquisition of movable property by prescription requires, among other things, five years’ possession in good faith. Article 3(2) of the Swiss Civil Code provides, however, that no one may invoke good faith if they failed to exercise the care required by the circumstances.
Here, several indications concerning the Pissarro’s provenance should have prompted an experienced collector such as Baron Thyssen-Bornemisza to make further enquiries. In particular, the information supplied by the Stephen Hahn Gallery did not account for the work’s provenance during the Second World War, while a label on the back of the painting suggested that it had passed through Berlin or Germany. Greater diligence was also called for in view of the known scale of Nazi looting and the particular vulnerability of Pissarro’s works to it. Because the Baron had not undertaken those checks, he could not rely on good faith and had therefore not acquired ownership by prescription under Swiss law.
That conclusion did not, however, resolve the dispute. The Foundation might subsequently have acquired ownership under Spanish law, independently of the defect in the Baron’s title. Subject to certain conditions, Article 1955 of the Spanish Civil Code permits ownership of movable property to be acquired after six years of continuous possession without requiring the possessor to be in good faith. The US courts accordingly held that the Foundation had acquired the painting by prescription under Spanish law, notwithstanding the Baron’s failure to acquire valid title under Swiss law. That conclusion is not final, however. Following the adoption of new California legislation concerning looted artworks, the US Supreme Court remanded the case in March 2025 for consideration of its effect on the applicable law.
(ii) Returning to the Modigliani
Let us return to the Modigliani. Swiss law differs considerably from New York law on this point. In New York, even a good-faith purchaser generally does not acquire title to a stolen artwork: a thief cannot transfer better title than they possess, regardless of the price paid or the purchaser’s lack of knowledge of the theft (Solomon R. Guggenheim Foundation v. Lubell, 77 N.Y.2d 311 [1991]; Angiolillo v. Christie’s). A possessor’s protection therefore rests principally on limitation periods, the doctrine of laches (see Section III above), and the demand-and-refusal rule (see Section III above), whose operation varies between states. A defendant may also contest the application of New York law in favour of a foreign law that permits acquisition in good faith.
In the Modigliani case, the defendants had argued that French law should apply because of the painting’s historical links with France or, alternatively, Swiss law because it had been kept in a vault in Switzerland. In an earlier decision, however, Justice Eileen Bransten applied New York law on the basis of an interest analysis, which identifies the state with the strongest interest in having its legal policy applied to the dispute. She noted, in particular, that the painting had entered the New York art market and had been offered for sale by Sotheby’s in New York in 2008. New York also had a particular interest in preventing its art market from becoming an outlet for stolen works.
As in Cassirer, the choice of applicable law was therefore decisive. Because that question had already been resolved at an earlier stage in Gowen v. Helly Nahmad Gallery, Justice Cohen did not revisit it in his decision of 3 April 2026. He focused instead on the merits under New York law.
The question remains how the dispute might have been resolved had Swiss law applied. In light of the case law discussed above, the purchaser’s good faith would probably have been central to the dispute. The work’s value, the purchaser’s professional standing and the inconsistencies in its provenance could have required enquiries beyond simply consulting the Christie’s catalogue. In our view, as in Cassirer, those circumstances could have led to a finding that the purchaser lacked good faith within the meaning of Article 3(2) of the Swiss Civil Code.
V. Conclusion
The Modigliani case illustrates the complexity of disputes concerning looted artworks. More than eighty years after the events in question, such cases continue to raise questions about the limits of property rights. The balance struck between remedying historical injustices, protecting good faith and ensuring the security of transactions ultimately depends on national legal traditions.
Recent legislation in France (Law No. 2026-351 of 9 May 2026) and the United States, including the Holocaust Expropriated Art Recovery Act of 2025, which notably abolishes the defence of laches, together with the establishment in Switzerland of the Commission for Cultural Heritage with a Troubled Past, demonstrates a genuine commitment by states to changing these approaches.