Milan fined over lasers and banners
The fine was also punishment for offensive banners which were unveiled at the San Siro insulting Leonardo, who was Milan coach last season and joined arch rivals Inter in December.
Serie A's weekly disciplinary release also confirmed that Napoli striker Edinson Cavani would be suspended for next Sunday's game at Bologna.
The Uruguayan scored a hat-trick in Sunday's 4-3 win over Lazio to keep his club in the title hunt but picked up a booking to take him over the limit.
Inter's Cristian Chivu and Milan's Antonio Cassano will both miss their sides' next match after being sent off in the derby.