The German city of Krefeld faces a potentially catastrophic legal battle that could cost hundreds of millions of dollars, as heirs of Dutch artist Piet Mondrian demand the return of eight valuable paintings in a lawsuit filed in Washington D.C. The case centers on four paintings currently held by the Kaiser Wilhelm Museum and four others that were secretly sold by former museum director Paul Wember in the 1950s. The plaintiffs value each of the eight Mondrian works at $50 million, based on recent auction results.

The lawsuit, pending since 2020 in a U.S. federal court in Washington, has created uncertainty for Krefeld's municipal government as residents prepare to elect their city council and mayor on Sunday. Social Democrat Frank Meyer, who has led the city administration for ten years, is seeking re-election for a second term. In April, the presiding judge indicated that a decision on whether to dismiss or proceed with the case is imminent.

The legal dispute has its roots in mysterious circumstances surrounding eight Mondrian paintings that likely arrived in Krefeld in 1929, when then-museum director Max Creutz planned an abstract art exhibition that never materialized. According to the heirs' claims, the paintings were either on loan or left in safekeeping without formal arrangements, meaning no transfer of ownership ever occurred. Paul Wember, who served as museum director from 1947 to 1975, claimed he discovered the eight paintings in 1950 under strange circumstances, though he never specified where they were found.

The trail to this legal battle began with Berlin-based provenance researchers Gunnar Schnabel and Monika Tatzkow, who discovered evidence of the paintings' unclear provenance while researching art dealer Sophie Lissitzky-Küppers. In 2017, they voluntarily presented their findings to the city in a report, advising officials to contact the Mondrian heirs as the likely rightful owners. However, all factions in Krefeld's city council have categorically refused negotiations with the heirs.

A 2019 scientific report commissioned by the city revealed the extent of the ownership problem. Two art historians found no evidence of municipal acquisition for the four paintings that have been listed in the museum inventory since 1954. They discovered no purchase contracts, donation agreements, or any documentation indicating a transfer of ownership to the city. The researchers found it highly improbable that Creutz had privately purchased such a large collection, as this would have been unusual for Mondrian and there is no evidence that the director, who died in 1932, maintained a private art collection of such magnitude.

The city's legal position relies entirely on German civil law's statute of limitations, which bars ownership claims after thirty years. However, American law does not recognize this concept, which allows someone to remain the legal owner while being unable to demand return of their property. Legal expert Peter Raue, commissioned by the city to present the provenance report, acknowledged that 'it is unclear whether the municipal museum acquired ownership' and that 'proof of Krefeld's ownership cannot be conclusively established with the information in the report.'

The case has revealed embarrassing gaps in museum documentation. Wember left the provenance section of the museum inventory blank, and legends he and his successors spread about the paintings' origins have been debunked. One persistent myth claimed that Creutz privately purchased the eight paintings and then donated them to his museum, but experts found no evidence supporting this story, which appears to have been invented to fill the provenance gap in municipal records.

Crefeld's position appears increasingly outdated in light of evolving international standards for art restitution. In disputes over Nazi-looted art, the consensus has emerged that public museums should not rely on good faith acquisition claims or mere passage of time to retain questionable works. The Prussian Cultural Heritage Foundation committed in the Guelph Treasure case not to invoke statute of limitations defenses in German proceedings, and the new arbitration agreement between federal, state, and municipal governments explicitly excludes such defenses.

City council factions justify their stance by arguing that the Washington Principles on Nazi-looted art don't apply because the case 'essentially predates 1933.' However, critics point out that Mondrian was likely deprived of control over his property after 1933, when his work was condemned as 'degenerate' by Nazi authorities. Moreover, they argue that museums should not retain works they cannot prove they legally acquired, regardless of Nazi connections.

The situation has created an ironic reversal of typical restitution cases. Researchers have identified owners of two of the four paintings Wember secretly sold, and negotiations are underway. One private owner has already accepted the heirs' claim, acknowledging that the city had no ownership rights when Wember made the sale. Meanwhile, Krefeld refuses to provide the transparent accounting that would be expected from a renowned merchant city, creating what observers call an 'upside-down world' where private collectors show more integrity than a public institution.