The move has seen Charlie Methven’s 5% stake in the club purchased in its entirety, while Stewart Donald’s has been reduced to 19%.
Juan Sartori has joined Louis-Dreyfus in increasing his stake in the club, with the latter now holding a 51% stake.
Louis-Dreyfus bought into the club in February 2021 and while he negotiated full governance control, it was confirmed earlier this year that he owned only 41% of shares.
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As of this morning, this has now increased to 51%.
This move also appears to signal the end of the controversial bid by 'The Fans Together' cryptocurrency group, who announced recently that they had agreed a price with Donald and Methven.
Louis-Dreyfus had responded to that bid by stating his close alliance with Juan Sartori moving forward. Sartori has now also increased his stake in the club, now owning 30%.
Sunderland have said that the governance of the club will remain unchanged.
A club statement from SAFC said: "Sunderland AFC today announces that Kyril-Louis Dreyfus has increased his ownership stake in the club to 51%.
"In parallel, Juan Sartori has increased his stake to 30%.
Governance remains unchanged.
"The shares have been acquired through the purchase of shares held by Charlie Methven, who has sold all of his shares, and Stewart Donald, who has sold down his stake to 19%."
Sunderland return for pre-season training on Wednesday as they look to step up their preparations for the first campaign back at Championship level.