The standoff between Caesars Entertainment and US businessman Carl Icahn has taken a further twist this week, with media outlets reporting that the ex-Tropicana Entertainment owner is now the largest shareholder of the company.

In a filing with the US Securities and Exchange Commission Icahn has taken his total stake in the Las Vegas headquartered organisation to 15.5 per cent, meaning he is also now obliged to obtain a gaming licence in the company’s home state of Nevada.

Icahn, who took an approximate 9.78 per cent of Caesars last month, is now thought to have taken his total investment in the company to close to $1bn.

After selling his Tropicana Entertainment business for $1.85bn to Eldorado Resorts last year, Icahn has continuously been pushing for a sale of Caesars, with the company stressing it “intends to carefully evaluate” the suggestion in February.

Upon securing his first stake, revealed in a securities filing this week by High River Limited Partnership and other entities affiliated with Icahn, he stressed a belief that Caesars stock is undervalued, was seeking board representation and urged that a new CEO not be appointed immediately.

A series of directorial changes were announced earlier this month, which saw Keith Cozza, Courtney Mather and James Nelson appointed to Caesars’ board of directors effective immediately.  

Subject to necessary regulatory approval, three existing directors were also announced to be stepping down from the board straight away, with the Icahn Group also holding the right to appoint a fourth representative to the board, if a new CEO, who is acceptable to new directors, is not named within 45 days of this agreement.

This is in relation to news that current incumbent Mark Frissora is to depart the role on April 30, unless the company exercises a one month extension.

Icahn said at the time of the appointments: “I believe the best path forward for Caesars requires a thorough strategic process to sell or merge the company, to further develop its already strong regional presence, which will allow Caesars to continue to take advantage of the Caesars Rewards program, bringing more and more players into Caesars’ Vegas market.

“I expect this to make Caesars the most powerful competitor in Vegas, the gaming capital of the world. Caesars would be a great opportunity for certain investors who have already expressed interest, and I’m glad the board will explore these opportunities.  

“Independent of strategic alternatives, I believe Caesars should also be focused on leadership succession, disciplined capital allocation, improving operating performance and optimising real estate and other assets.”

Last year Caesars rejected moves by Tilman Fertitta, the billionaire owner of the Golden Nugget Casinos empire, who was seeking a merger of the two companies.