The contract to operate the system was made with Ansaldo STS, who has subcontracted it to Metro Service, a joint venture between them and Azienda Trasporti Milanesi (ATM), the public transport company of the city of Milan, Italy.
Kontrak untuk mengoperasikan sistem dipegang oleh Ansaldo STS, yang memeberikan sub kontrak kepada Metro Service, sebuah joint venture antara mereka dengan Azienda Trasporti Milanesi (ATM), sebuah perusahaan transportasi umum di Milan, Italia.