Mark Ein, an investor originally from Chevy Chase, added a minority stake of the Orioles to his growing athletics inventory that includes the NFL’s Washington Commanders, Premier League’s Leeds United and the Mubadala Citi DC Open tennis tournament.

The size of Ein’s stake in the Orioles is not known, but he’s the newest investor to join an ownership group led by private equity billionaire David Rubenstein of the Carlyle Group. When Rubenstein’s group purchased the Orioles last year, it was valued at $1.7 billion.

The Orioles confirmed the minority acquisition of the club by Ein, as Bloomberg first reported. Ein did not respond to a request for comment. In a social media post, Ein wrote that he was “Thrilled to become part of the historic ⁦[Orioles] franchise, the team I cheered for as a young boy growing up in Maryland.”

View post on X

Ein has a connection with Rubenstein, who through a spokesperson did not respond to a request for comment. Ein worked at the Carlyle Group early in his career, the company Rubenstein co-founded, before Ein created Venturehouse Group in 1999.

Advertise with us

In 2023, Ein became a limited partner of the Commanders, joining a group led by Josh Harris. In a statement at the time, Ein said: “Can’t wait to help make the team as beloved throughout our DMV community as it was when i [sic] had my best childhood memories going to games with my dad as a little boy.”

Ein is also the owner of Washington City Paper. He leads the World TeamTennis organization Washington Kastles and he became an investment partner for Leeds United in 2024.

The ownership group leading the Orioles is robust. It includes billionaires Michael Arougheti and Michael Bloomberg, as well as Arougheti’s colleagues at Ares Management Corp., Mitchell Goldstein and Michael Smith. It also has former athletes in Orioles Hall of Famer Cal Ripken Jr., and NBA Hall of Famer Grant Hill.

The group has a full to-do list this winter. Baltimore is searching for a manager and additional front-office help underneath president of baseball operations Mike Elias. Plus, considerable investment may be required to help the Orioles return to the postseason in 2026 after a dismal 2025.