They also noted the "presumption" is Tsai will utilize the option to take over controlling interest.
The agreement, first reported by ESPN, would see Tsai take over majority control of the team in four years and could open the door to him relocating the Nets franchise to San Diego, which has not had an National Basketball Association team since the Clippers relocated to Los Angeles in 1984.
Russian billionaire Mikhail Prokhorov will remain the principal owner of the team for four more years, and will hold on to his responsibilities to oversee business and sports operations, ESPN said. Current owner Mikhail Prokhorov is expected to retain control of the team until then.
The Nets declined to comment.
The sale does not include the Barclays Center. He bought the minority stake of the team and the majority stake of the arena from real estate developer Bruce Ratner in 2015 at a cost of $1.7 billion.
The Nets' local revenue was a league-low $36 million last season, and the team earns only $20 million from its local television contract with YES.
The Nets never did become title contenders, but those deals would hamstring the team for years. He received both undergrad and law degrees from Yale and has Canadian citizenship.
Tsai, who has formally expressed his support for the team's new general manager, Sean Marks, and coach Kenny Atkinson, reportedly plans to help with efforts to turn the team around. Prokhorov has a net worth of $11.3 billion, according to the Bloomberg Billionaires Index.