The portrait of the old man, which was the most damaged of the five in the theft and sustained deep scratches, has over the years been attributed to Jan Lievens and to Ferdinand Bol, a pupil of Rembrandt. But Timo Trümper, the curator of the exhibition, says analysis of the painting style has ruled out either artist as the author of the work. The attribution to Bol stems from the artist’s signature on the back, but Trümper says that may indicate that he owned the portrait, not that he painted it. He says Bol may have obtained the work after Rembrandt’s bankruptcy in 1656. 

The painting is very similar to a work at the Harvard Art Museums in the US. That work bears Rembrandt’s signature, although its attribution has also been a matter of debate. Trümper says that under-painting on the Gotha work indicates that it may have been the original, and that the Harvard painting is a later studio copy. 

“It’s a question of interpretation,” he says of the Gotha work. “We can be sure it originated in Rembrandt’s studio—the question is how much of it is Rembrandt and how much his pupils? We have already talked to a lot of colleagues. Half say: ‘No, it’s not Rembrandt, it’s one of his pupils.’ The other half say it’s an interesting theory and they can’t rule it out.”