Consolidated Press Holdings has completed its purchase of 50% of Blackcourt League Investments, with James Packer taking over from Peter Holmes à Court as Rabbitohs co-owner.

The Rabbitohs have confirmed billionaire James Packer has bought out the 37.5 per cent share in the foundation club previously owned by Peter Holmes à Court.

Packer's investment in Souths looms as a massive boon for the club, and comes just weeks after the Rabbitohs broke their 43-year premiership drought with a grand final triumph over the Bulldogs.

The buy-out of Holmes a Court's share in the club means Packer joins Russell Crowe as co-owner of the Blackcourt company, which holds a 75 per cent controlling stake in club, with Packer's purchase rumoured to be in the vicinity of $7.5 million.

Rabbitohs' members will still maintain their 25 per cent share in the red and green outfit, with the football club still maintaining the final say on the team’s name, logo, colours, jersey and choice of home ground.

Souths chairman Nick Pappas, who took on the might of News Corp as the Rabbitohs fought a two-year exile from the competition at the turn of the century, hailed the announcement of Packer's involvement as a proud day for the club.

“I join with the Rabbitohs senior management team, our staff and our Members in welcoming James Packer to the Rabbitohs family," Pappas said.

"We promised some years ago to deliver sustained on-field success and the first chapter of that story was written on 5 October 2014 with our 21st premiership. We also promised to connect our great club with the highest echelons of Australia’s business community so that its longevity could be ensured for decades to come. This we deliver today."

The Crowe-Packer partnership gives the Rabbitohs a level of clout rarely seen in rugby league, with the pair's status and connections on a global scale set to ensure the club's long term survival.

Packer's father Kerry was an ardent supporter of the cardinal and myrtle, and on Thursday the 47-year-old described his appointment as co-owner of the club as an honour.

"This is a very proud day for my family," Packer said.

"My father had a long history and association with Souths and to now be a co-owner with Russell Crowe and the Members is an honour and a privilege.

"I am hopeful that working together with Russell, Souths Chairman Nick Pappas and CEO Shane Richardson, we can win more premierships for the fans, secure the club’s long term financial future and in time establish Souths as Australia’s number one football club; with the biggest supporter base for all codes.

"Can I put on record my gratitude to Peter Holmes à Court for the outstanding work he has done at Souths over many years and wish him well for the future."