Ospreys are "thrilled by the opportunities ahead" after Asian-based sports marketing group Y11 Sports & Media bought a 75.1% stake in the Welsh region.
Ospreys chairman Rob Davies will remain in his role as he and pre-existing shareholders collectively retain a 24.9% stake, with chief executive James Davies-Yandle and financier Donald Tang added as directors on the Guinness Pro14 club's board.
A new holding company - Ospreys International Group - has been established after the "multi-million-pound" deal, with all the financial benefits made to be put back into the club.
Davies said: "Since the advent of regional rugby, the Ospreys have always aimed to be its pioneers.
"We haven't been afraid to do things differently and to push the envelope. Today's announcement is us doing the same again.
"It was essential we found a partner who shared our ambition and vision, but with the cultural understanding, expertise and resources to propel the region and community all into a new era.
"We needed to secure the success of the past, whilst embracing fully the future and that is what we are now doing together. We're thrilled by the opportunities ahead."
Davies-Yandle added: "It's an exciting time for the Ospreys: its team, its supporters, the organisation as well as for the game of rugby."
Meanwhile, Scarlets head coach Brad Mooar and eight players - including centre Hadleigh Parkes - are to leave the club before training resumes.
Forwards coach Ioan Cunningham will also not return to Parc y Scarlets with the club moving forward with coaches and players for the 2020-21 season after they return from the enforced break due to the coronavirus pandemic.
Mooar was due to link up with Ian Foster's New Zealand coaching team and was being replaced by Glenn Delaney.
Players Parkes, Kieron Fonotia, Corey Baldwin, Jonathan Evans, Morgan Williams, Simon Gardiner, Rhys Fawcett and Tom James, who is retiring from professional rugby, are also leaving.