The Hall of Fame recipient has reportedly maintained a relationship with Bertarelli since Alinghi's America's Cup loss to Oracle in the 2010 Deed of Gift challenge.
His experience is seen as a crucial factor in what could be a young Alinghi team.
Butterworth also brought his know-how to Luna Rossa at the America's Cup in Auckland this year, acting as a facilitator between the hosts and local authorities.
According to Italian media, Alinghi are also negotiating the purchase of Team NZ's first generation AC75.
There has also been speculation that Alinghi's challenge will come with the reputed backing of the Red Bull Formula 1 team, who have just seen their driver Max Verstappen beat Lewis Hamilton to claim the F1 world championship on Monday.
Alinghi's return could reignite another rivalry with Challenger of Record Ineos Britannia, who worked with Hamilton's Mercedes team ahead of their America's Cup challenge in Auckland earlier this year.