In August, Craig Horwitz made 25 winning identical first four bets on Race 7 at Warwick Farm via Sportingbet's internet site from his Sydney home. He won, and he claims his $800 outlay should have netted him $510,992.50, based on the declared dividend of the Tote.

However, Sportingbet limited his payout to $50,025. The betting agency cited a clause in its betting rules, unknown to many gamblers including Horwitz, that it pays a dividend, as declared by the selected tote that is capped at $50,000 per client per event.

Horwitz is claiming that Sportingbet has breached its contractural obligations by not paying him the declared dividend of $510,025.

He has engaged Middletons' partner Murray Deakin as his legal counsel. It is expected that if the matter is heard in the Federal Court, it will be an important test case of the unfair contracts provisions under the new Trade Practices Amendment (Australian Consumer Law) Act (No.1) 2010, which came into effect on 1 July.

The new laws also gave increased powers to the ACCC.

"I believe this is the first case to be brought under the new unfair contract regime," Deakin said. "Mr Horwitz's misfortune provides an ideal vehicle to test the interpretation and application of the new unfair contracts terms legislation."

Deakin added that Australian gamblers needed to be aware of the liability cap Sportingbet has in place, and cast skepticism upon the betting agency's claim that "there is no better bet than a Sportingbet".