Maverick Carter, LeBron James’ longtime business manager, is advising investors aiming to launch a global basketball league to rival the NBA, according to reports from Front Office Sports and Bloomberg. The group is seeking to raise $5bn from private equity funds, sovereign wealth funds and wealthy individuals.

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The proposed league would feature six men’s and six women’s teams playing in eight international cities, rotating every two weeks. Singapore is among the planned locations. The format is modeled after Formula 1’s global schedule, designed to create a premium, international basketball experience.

Despite Carter’s role, Front Office Sports confirmed LeBron James is not involved. James, who has expressed interest in owning an NBA team after retirement, currently holds a player option for the 2025-26 season. Carter, meanwhile, has expanded his business ventures beyond sports, producing several of James’ TV and movie projects.

Notable backers include Skype co-founder Geoff Prentice, former Facebook executive Grady Burnett, and SC Holdings’ Jason Stein and Daniel Haimovic. UBS Group AG and Evercore Inc are managing fundraising efforts.

Bloomberg reported that the investment group might try to tap private equity and sovereign wealth funds to raise the $5bn it is seeking; currently, private equity funds are limited to a 20% stake in NBA teams and are not allowed to serve in ownership roles.

The NBA hasn’t faced a major rival since absorbing the ABA in 1976. Previous attempts to challenge dominant US sports leagues, including football leagues that tried to compete with the NFL, have largely failed. In women’s basketball, the ABL briefly competed with the WNBA in the 1990s but folded after two seasons.

The rise of the 3-on-3 Unrivaled league, which debuts on Friday featuring several WNBA stars, highlights growing interest in alternative basketball formats.