A UK judge says a Giotto painting worth £10 million ($13.2 million) isn’t going anywhere but home. In a decision delivered on Monday, Judge Justice Carr upheld the Arts Council England’s refusal to grant an export license for the work, which is currently in Britain. But unlike most export disputes in the UK, this isn’t a matter of trying to preserve a treasure for the nation. The question, instead, is whether the artwork was in the country legally to begin with.

According to the ruling, the painting, titled Madonna and Child, was illegally exported from Italy in 2007. Therefore, the UK cannot grant a new export license other than to facilitate its return there, the Guardian reports.

In 1990, Kathleen Simonis purchased what was then identified as a 19th-century Giotto copy for just £3,500 ($6,400) at a Florence auction. Two years later, art expert Filippo Todini published an article proclaiming the work to be an authentic Giotto, an attribution that was later given more weight by technical analysis during restorations and saw the work’s value skyrocket.

Italy granted an export license in 1999, but came to realize, as Carr wrote in her ruling, that this was a work “of exceptional cultural and historical importance.” The export license expired in 2004, but an Italian ministerial decree the same year prevented the painting’s export.

The painting traveled to London in February 2007, days after a ruling from the Tribunale Amministrativo Regionale di Lazio annulled the 2004 decree. Simonis’s lawyers wrote a letter interpreting the ruling to mean that the painting’s export 1999 license was now automatically extended while litigation was underway. Simonis did not inform the Italian export office of her plans and instead sent the painting to the UK posthaste.

The issue of whether the export had been legal arose almost immediately, as Italy demanded the painting’s return once it learned what had happened. In November 2008, Italy’s highest administrative court, the Consiglio di Stato, reversed the previous year’s ruling,

In 2015, Simonis applied to the Arts Council England to permanently export the painting to a free port in Switzerland, which is not in the EU. The council found it did not have the ability to issue such a license. The new ruling upholds the council’s finding that only Italy has the authority to allow the painting’s export outside the EU because the export to the UK was not lawful.

This leaves Simonis in an undesirable spot. Italy can’t force her to return the work, because the statute of limitations is up, but they will almost certainly refuse to grant her an export license for what they feel is a national treasure.

“The painting is effectively unsellable,” wrote Alexander Herman in a blog post for the Institute of Art & Law. “The only potential buyer would have to be UK-based, someone who doesn’t mind the stink of it having been unlawfully exported from Italy.”