The painting is signed ”L da Vinci” with the underlined letters ”Pinxt” directly below. Pinxt is an abbreviation of the Latin word Pinxit. Pinxit (from Latin: ”one painted”) is a stylized amendment added to the signature depiction of the name of the person responsible for a work of art, found conventionally in the late middle ages and the renaissance. It is known that Leonardo signed some sketches with ”I des,” which suggests ”Io designato,” that is, ”I drew this.”¹

The signature was discovered in 1994 using very strong light. It is not visible in normal light. In strong light only the last i in Vinci is visible. In 2019 we started an in-depth analysis of the signature.

Raman spectroscopy performed on the signature found only one pigment, carbon.

Paintings conservator Ann-Marie Mild, SVK (Studio Västsvensk Konservering), Gothenburg, who made the UV/IR report, states: ”Photography in infrared (IR) shows retouches more clearly than in visible light. However, no underlying painting or drawing is visible. This is better seen on the X-rays. However, the part of the painting where the signature is located does not appear to have been retouched. This part is not changed, however the signature may have been painted on during a previous restoration or it may have been there before. Nothing speaks against that the signature has been there from the beginning. The signature is most certainly under the current varnish.”, see UV/IR report below.

So far we have found no indication that the signature is spurious. The photo of the signature was taken in very bright light. Hue, saturation, brightness and contrast have been modified to enhance the letters. Microscopy, see photomicrograph below.

¹Raymond Stites. The Sublimations of Leonardo da Vinci. Smithsonian Institution Press, 1970, 10.