Giovanni Francesco Penni ( 1496 - 1528 ) was an Italian painter. Giovanni Francesco Penni s works have been put up for auction numerous times, with realized prices surpassing estimated prices, varying from 3255.42 USD for Hercules kneeling before a snake in 2004 to 42932.63 USD for Heilige Sippe in 2006 , based on the size and medium of the artwork.