Toulon's Mourad Boudjellal has sold his controlling share in the French Top 14 club but, under the terms of the deal revealed on Monday, remains the club president.
The 80-year-old pharmaceuticals magnate Bernard Lemaitre, who already held a 44 percent stake in Toulon, is now the majority shareholder.
"The Top 14 requires significant financial capital, especially to provide our club with high-level sports infrastructure," explained Boudjellal.
Lemaitre had already financed the construction of Toulon's new training centre which will open next June.
"I am pleased that Bernard Lemaitre's collaboration allows us to compare ourselves to the best clubs in Europe," said Boudjellal, who will stay on as president at least until the 2020 elections for the presidency of the French national league.
Should he win that, Boudjellal would be obliged to step away from Toulon.
His 12-year tenure at the 111-year-old club has brought unprecedented success with three European Cups and France's Top 14 title in 2014.
Since taking over sole control in 2007, Boudjellal has bought a series of world class players such as Ma'a Nonu, Sonny Bill Williams, Jonny Wilkinson and Bryan Habana.
His latest headline capture was South African World Cup winner Eben Etzebeth.
Toulon are currently sixth in the Top 14 after a 19-9 win at Pau at the weekend.
Mourad Boudjellal has sold his majority shareholding in Toulon but stays on as the club president