Times Online has reported: "A fingerprint in the top left corner of this portrait appears to have confirmed it. The 13 x 9in picture, in chalk, pen and ink, was catalogued as 'German school, early 19th century'. It sold for $19,000 in 1998. Now some leading art experts agree that it is almost certainly by Leonardo da Vinci and worth about 158 million." Read the rest of the story here:
Looks like a Leonardo to me!