If you can’t spot the sucker after 20 minutes at the poker table, chances are the sucker is you. Investors that bet on online gaming companies at the height of the US poker craze in the mid-2000s learnt that the hard way.

In 2005, when they first listed, the founders raked in millions. A year later, punters were left with the stock market equivalent of a busted flush when US authorities cracked down on what was a technically illegal industry. Poker groups cried foul but to no avail.