When billionaire Rob Walton bought the Denver Broncos four years ago, he didn’t hesitate to flex his financial muscle. The 81-year-old, who Forbes estimated was worth $65 billion in 2022, paid a then-record $4.65 billion for the NFL franchise, reportedly outbidding the next best offer by at least $400 million. In retrospect, the purchase price seems like a bargain with the NFL franchise now worth $6.55 billion per Sportico’s valuations.
But Walton has quietly continued that sports spending spree. Two years ago, he purchased a stake in the Arizona Diamondbacks, according to multiple people familiar with the transaction, an investment that was never publicly announced.
The richest owner in major U.S. sports, Walton bought a 10% piece of the MLB franchise at a $2 billion valuation, said the people, who were granted anonymity because the matter is private. The team used the bulk of the proceeds for stadium improvements at the Diamondbacks’ home venue, Chase Field. Arizona ranked 24th on Sportico’s list of MLB’s most valuable teams last year, with an enterprise value of $1.54 billion.
Walton declined to comment. A representative for the team, which is controlled by managing general partner Ken Kendrick, did not reply to a request for comment.
While a nine-figure check may seem outsized for some investors, it’s chump change for Walton, who is now worth roughly $146 billion, according to Forbes. The son of Walmart founder Sam Walton, Rob and his fellow heirs collectively own around 45% of outstanding shares in the retail giant, which currently has a market cap north of $1 trillion.
Kendrick, 82, made his fortune in software and banking, founding the company that would eventually become Ellucian and investing in Woodforest National Bank. Kendrick was part of the initial group that brought the expansion franchise to Arizona in 1995 and, nine years later, bought control of the Diamondbacks in a transaction that valued the club at $238 million. Forbes pegs his net worth at $1.2 billion.
It’s unclear whether Kendrick plans to cede control at any point in the future, and whether Walton would pursue team control if so. Walton stepped back from the Broncos in 2023, transferring control ownership of Denver to his son-in-law, Broncos CEO Greg Penner. Walton has also wound down his involvement in Walmart, retiring from a 23-year stint as chairman in 2015 and leaving the company’s board in 2024.
However, he’s still adding to his sports empire. In May, Walton was announced as an investor in the Motor City Golf Club, the first expansion team and seventh overall in the TGL, the team-based golf league founded by Tiger Woods and Rory McIlroy’s TMRW Sports.
And while minority sales tend not to reflect control sale prices—because discounts or, in some cases, premiums are applied—Walton’s Diamondbacks deal could have a cascading effect on the next major transaction in MLB. The San Diego Padres are currently on the market, over two years after the death of control owner Peter Seidler. Sportico previously reported that billionaires Dan Friedkin, Joe Lacob and José E. Feliciano are among those interested in buying the franchise, which ranked 10 spots ahead of the Diamondbacks in MLB team valuations at $2.31 billion.