Billionaire Len Ainsworth jokes he will be cutting back to only five days a week in the office, a week after receiving a $473 million cheque for the sale of most of his shares in Ainsworth Game Technology.

The sale finalises the agreement the 94-year-old Financial Review Rich List member struck in February 2016 to sell most of the shares in the poker machines manufacturing firm he established two decades ago to Austrian giant Novomatic.