Tether, the cryptocurrency firm, made an offer worth about €1 billion (nearly $1.2 billion) for the Agnelli family's majority shares in the record 36-time Italian champions.
"Juventus, our history and our values are not for sale," said John Elkann, chief executive of Exor, the Agnelli family's holding company, in a video message posted on Juventus' website.
"Juve has been part of my family for 102 years," Elkann added. "Over the course of a century, four generations have emboldened it, made it strong, taken care of it in tough times, and celebrated it in the many festive moments.
"We continue to support our squad and are looking toward the future in order to build a winning Juve," added Elkann, the grandson of Fiat tycoon Giovanni "Gianni" Agnelli.
Juventus have not won Serie A since taking nine straight titles between 2012 and 2020. The Turin club fired Igor Tudor and hired Luciano Spalletti last month after a difficult start to the season.
Former Juventus president Andrea Agnelli and the club's entire board of directors resigned in 2022 amid a false accounting inquiry.
Several of Italy's other major clubs -- AC Milan, Inter Milan, Roma -- are owned by foreign investment firms. Juventus and defending Serie A champions Napoli, who are owned by Italian film producer Aurelio De Laurentiis, are the main holdouts.
"Exor reaffirms its previous, consistent statements that it has no intention of selling any of its shares in Juventus to a third party, including but not restricted to El Salvador-based Tether," Exor said in a statement.
"Juventus is a storied and successful club, of which Exor and the Agnelli family are the stable and proud shareholders for over a century, and they remain fully committed to the club, supporting its new management team in the execution of a clear strategy to deliver strong results both on and off the field."
