Billionaire publican Bruce Mathieson has made a $100 million investment in The Star Entertainment Group, following Bally’s Corporation tipping in $200 million to save the casino operator.

Mathieson’s company Investment Holdings is already Star Entertainment’s largest shareholder. He has been gradually upping his stake in the casino and already holds around a 10% share.

The Australian’s DataRoom estimated Mathieson stood to lose about $150 million if Star collapsed. His 15% stake in Endeavour Group has also been causing issues, with its share price dropping to about $3.82 this week and its market value at $7.2 billion, half the price it was listed at in 2020.

The Australian released its Australia’s Richest 250 of 2025 list last month, which revealed the big wins and losses that drinks billionaires have recorded over the past 12 months.

In 73rd place on the list is was Mathieson ($2.21 billion), the founder of ALH Group, who was one of only two drinks billionaires to see his wealth decline in the last 12 months – down from $2.55billion in 2024 and $2.90billion in 2023.

As The Australian noted: “Mathieson is agitating for change at Endeavour Group, the listed pubs and liquor outlets group that accounts for most of his wealth, and hoping for change at Star Entertainment, the casino group he has racked up big losses in.”

US-based casino giant Bally’s Corp owns 19 casinos in the US and operations in the UK with about 17,700 poker machines, 630 table games and 3950 hotel rooms.

Bally’s said its buyout of Star Entertainment would allow the business to regain its position as “Australia’s preeminent gaming destination.”

The company “will invest in and partner” with Star as it applies its “proven track record of revitalising underperforming casino businesses”.

“Bally’s will continue to work collaboratively with regulators and stakeholders to support a successful turnaround of The Star,” the company said in a statement.

“Strategically, the transaction is intended to preserve The Star’s long-term potential, with Bally’s committed to leveraging its operational expertise to deliver a more resilient and sustainable business for all stakeholders.”

Bally’s chairman Soo Kim said Star’s casinos in Sydney, Brisbane and Gold Coast would need to be turned around but could start making money “within a reasonable amount of time”.

“The definition of insanity is doing the same thing over again and again and expecting a different result,” he said.

“We need to put different executives in there – this particular mix of executives have generated poor operating performance.”

“We are ready to go and have always been ready to go,” Bruce Mathieson jnr told the Australian Financial Review. “The hardest part has been dealing with the incumbent board and management.

“They are great, irreplaceable assets that obviously have been mismanaged. We hope to be able to bring some stability, vision and investment with a good, aligned team.”

Shares in Star Entertainment are expected to resume trading this week after being suspended since early March by the ASX due to the company’s failure to lodge its half-year accounts.