Identical lesions of the nails were observed in three patients. The main signs were a yellow colouration along the entire length of the nail plate with splinter haemorrhages in its proximal portion, a tendency towards transverse overcurvature of the affected nails, and exposure of a matrix tumour after the nail had been avulsed and the proximal nail fold turned back. The nail signs were striking enough to lead to the clinical suspicion of a filamentous tufted tumour in the matrix of a funnel-shaped nail, an entity not previously described.