Sunderland chairman Kyril Louis-Dreyfus has increased his shareholding in the club to 51%, amid interest in the Black Cats from a cryptocurrency group.
"Today marks an important step as we continue to rebuild Sunderland AFC," Louis-Dreyfus said in a statement.
"Our ownership group has been consolidated and there will be no further sale of shares to a third-party buyer.
"We remain committed to our strategy of delivering long-term success and sustainability and together, alongside our dedicated staff and loyal supporters, I believe we can now move forward as one unified football club."
In addition to Louis-Dreyfus increasing his share in the club, co-owner Juan Sartori has, in parallel, increased his own stake to 30%.