Italy's Benetton family and U.S. investment fund Blackstone announced in April a 58 billion euro ($58 billion) buyout offer for Atlantia, to take it private and stave off rival interest for the airport and motorway operator.

They are offering Atlantia's investors 23 euros per share.

Earlier this week the Italian market watchdog cleared the buyout bid prepared by the Benettons, which already owns a 33% stake in the infrastructure group, and the U.S. investment fund.

The offer is set to start on Oct. 10 and end on Nov. 11. ($1 = 1.0063 euros)

(Reporting by Elisa Anzolin, editing by Keith Weir)