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The Carolina Panthers are on pace to become the most expensive franchise in U.S. sports history, with bidding for the team climbing above $2.5 billion, Bloomberg News' Scott Soshnick reported Wednesday.

According to Soshnick, a group headed by Michael Rubin has dropped out of the bidding process. Rubin is the executive chairman of apparel company Fanatics.

Current Panthers owner Jerry Richardson announced last December he was putting the team up for sale at the conclusion of the 2017 NFL season. Should the final price of the Panthers hit $2.5 billion or more, it would eclipse the $2.2 billion Tilman Fertitta paid to buy the Houston Rockets last September.

A $2.5 billion bid wouldn't be too far off the perceived value of the Panthers. Forbes estimated in September the franchise was worth $2.3 billion, which was up 11 percent from the year before.

Music star Sean "Diddy" Combs and Golden State Warriors star Stephen Curry expressed interest in joining a Panthers ownership group, but it appears that pursuit has ended. The Charlotte Observer's Rick Rothacker and Jim Morrill reported earlier this month Diddy had signed on with Rubin, with Curry potentially joining them.

According to Soshnick, at least three people remain in the race: Bedrock Industries LP CEO Alan Kestenbaum, Appaloosa Management LP founder David Tepper and Sherman Financial Group CEO Ben Navarro.