As part of the deal, Andrew Gordon, the son of WIN owner Bruce, will take over as the club's chairman.

Ex-Dragons CEO Brian Johnston will return to his former job, replacing Peter Doust.

"Today is a momentous day in the history of the St George Illawarra Dragons as we welcome WIN as a partner in our club," Johnston said via statement on Monday.

"The Gordon family through WIN bring a great passion for the Dragons and have been a supporter of rugby league for decades, first with the Steelers in 1982 and then the Dragons."

Dragons coach Paul McGregor hailed the new owners after they agreed to buy a 50 per cent stake in the NRL joint venture.

"It's really positive going forward with such a strong organisation as WIN Corp and the Gordon family being big supporters of rugby league," McGregor told Macquarie Sports Radio.

"The growth there in the business behind the football team will improve, so it's a positive all round for everyone involved in the club.

"Not too much will change.

"Brian Johnston coming on board as the new CEO, he's a very experienced ex-player and businessman and his attitude towards everything is really good to be around.

"It's all systems go for us because everything is all about winning with WIN."

Doust, who earlier in the year announced his plans to retire at season's end, has been a lightning rod for criticism during recent years with "Oust Doust" banners a frequent sign on the hill at Dragons games.

As part of the deal, the Dragons' $6 million loan to the NRL will be repaid.

WIN will take over the Illawarra Steelers' share of the club and will have three seats on the board, however, it is not expected to result in a change in the club's name or brand.

Games will continue to be played in Wollongong at WIN Stadium and Kogarah's Jubilee Oval.

Australian Associated Press