In a surprising move, the Boston Celtics' ownership group, Boston Basketball Partners LLC, has revealed plans to sell the team, according to a statement posted on the Celtics' social media account on Monday. The majority stake in the franchise is expected to be sold by the end of 2024 or early 2025, with the remaining sale to be completed in 2028.

The decision to sell the team comes from the controlling family of the ownership group, citing "estate and family planning consideration" as the driving factors behind the move. As one of the most successful and widely-followed teams in U.S. professional sports, the Celtics are expected to garner significant interest, potentially commanding a high price in the competitive market of sports franchise valuations.

Under the leadership of the ownership group's head, Wyc Grousbeck, the Celtics have enjoyed tremendous success on and off the court. Grousbeck, who led the group to acquire the team for $360 million in 2002, expressed his commitment to remain as the team's governor until the second closing of the sale in 2028.

It should be noted that Grousbeck is also part of the ownership group behind the tequila brand Cincoro, which includes NBA team owners and Hall of Famer Michael Jordan.

Representatives for Grousbeck and the team have not responded to requests for comment at the time of writing.

The Celtics' most recent triumph came in June when they clinched their 18th NBA championship by defeating the Dallas Mavericks in Game 5 of the Finals. This victory marked the team's second championship under Grousbeck's ownership, further enhancing the franchise's prestige and market value.

The sale of sports teams, particularly those in the National Football League (NFL) and the NBA, has witnessed skyrocketing valuations in recent years. Notably, in 2023, the NBA's Phoenix Suns and WNBA's Phoenix Mercury were sold for a record valuation of $4 billion. This trend is largely driven by the lucrative media rights agreements and the increasing popularity of live sports broadcasts.

As negotiations surrounding the NBA's media rights are underway, an announcement regarding new deals is expected soon. Potential bidders, including Comcast's NBCUniversal, Disney's ESPN, and Amazon's Prime Video, are vying for the rights, with NBCUniversal rumored to be offering $2.5 billion per year.

The future ownership of the Boston Celtics remains uncertain, but with their esteemed history and recent success, basketball fans and industry insiders will be closely monitoring the developments of this high-profile sale.

Please note that this article is based on the information provided and does not include any additional information beyond what has been mentioned.