A director of retail optical group George & Matilda Eyecare, owned by unlisted public company IPIC Holdings Limited, has racked up a gambling debt of $16.2 million, according to The Sydney Morning Herald newspaper.

The director, Mr John McGrath, 54, is primarily the founder and head of Australian Share Exchange-listed-company McGrath Real Australia Limited, and is reported by The Herald as owing the biggest debt in gambling history by a single person to a single company in Australia.

The huge debt is owed to Tom Waterhouse-run company William Hill Australia, and, while a secret until now, has been rumoured in racing circles for some months.

Mr Waterhouse declined to answer questions on the matter, citing responsibility to clients.

McGrath Real Estate Limited was floated on the ASX in 2005 at $2.10 a share, which has fallen to as low as 48 cents. That company’s chairman, most of its directors and its chief executive officer all recently announced their imminent resignations.

Two days after The Herald’s story, Mr McGrath said in an email sent to staff and seen by The Australian newspaper: “The information in the article so ridiculous … I will deal with it and its authors.”

In addition to Mr McGrath, the directors of IPIC are Messrs Andrew Reitzer (chairman), Christopher Beer, Peter Papas and Geoffrey Green.