Billionaire pokies king Len Ainsworth has sold his 53 per cent stake in Ainsworth Game Technology, the company he founded two decades ago, to Austrian gaming company Novomatic. Based in Vienna, Novomatic is the world’s second largest poker machine manufacturer.

The deal includes Ainsworth retaining his role as chairman, with Novomatic saying it expects to keep its stake in the company at about 53 per cent and retain Ainsworth’s ASX listing.

The 92 year old veteran, the world’s oldest pokies magnate, plans to donate a large chunk of his $473 million windfall to health research as well as sharing some of the cash with his family.

“I take the view I’ve been lucky in life and I should share my luck with my family,” Mr Ainsworth said. “I think medicine and universities would be the target. If you can find a cure to something, that is a big prize in itself.”

Mr Ainsworth has given away more than $30 million to medical research, including a donation to the redevelopment of Sydney’s St Vincent’s Private Hospital.

The pokies entrepreneur’s family wealth was estimated at $1.82 billion in the BRW 2015 Rich List. In the 1990s he handed his family a lucrative stake in Aristocrat Leisure, which Mr Ainsworth founded, upon discovering he had been diagnosed with prostate cancer.

The diagnosis famously proved false and Mr Ainsworth went on to create his second pokies empire, Ainsworth Game Technology, which competes head to head with Aristocrat.

Mr Ainsworth sold 172.1 million shares at $2.75 a share, netting the entrepreneur more than $470 million.