CHICAGO (AP) — A federal judge in Chicago is set to issue a verdict in a peculiar civil trial over a celebrated Scottish-born artist’s insistence that he did not paint a landscape work that was once valued at more than $10 million.

The painting’s owner, a prison official who paid $100 for in the mid-1970s, sued painter Peter Doig (DOYG’) for millions after the work’s projected sales price tanked when the 57-year-old artist disavowed it.

Authenticity disputes typically arise after artists die, making this case all the rarer in the art world. The judge planned to announce his decision Tuesday.

Robert Fletcher says he acquired the painting from a 16-year-old Doig around 1976. But one witness testified her now-deceased brother, whose name was similar to Doig’s, painted it.