The Central Bank is wont, on occasion, to warn on the risks to small investors of getting into "speculative" financial derivatives such as contracts for difference.

That hasn't put off some of the world's largest investors. These instruments, which allow investors to take highly-leveraged bets on various investments from stocks to foreign exchange rates, are beloved by money managers from BlackRock and Fidelity Investments.

In the last nine months, finally, investors have been obliged to disclose when their stakes in Irish companies, including CFD holdings, top 3 per cent. Up until last November, they only had to reveal actual stock holdings. It’s been a long time coming.

The family of Ireland's then richest man Seán Quinn clandestinely built up a 28 per cent stake in Anglo Irish Bank between 2006 and 2006 using CFDs.

As the value of the shares underpinning the bet plummeted, the Quinns were forced to cover their losses with the CFD brokers.

This was largely funded by Anglo Irish. In an effort to draw a line under the crisis, the bank also funded the conversion of much of the wager into actual shares. It also facilitated the placement of a 10 per cent stake in the bank in 2008 to a group of 10 developer clients to further unwind the Quinn CFD position.

Quinn said in February 2014 that, all told, his family lost €3.2 billion on its leveraged investment in Anglo Irish, which was nationalised in 2009 and put into liquidation four years later.

"I was a fool," Mr Quinn told a court trial at the time, which ultimately led to the conviction of two former Anglo Irish bankers for their involvement in the illegal lending of money to the 10 developers to buy shares in the bank.

The episode highlights the extreme end of risks associated with CFDs. But it’s mindboggling that while the State first enacted enabling legislation in 2009 to get rid of a loophole that allowed CFD stakebuilding go undetected, it was never acted on.

Instead, it took a further seven years before the practice was outlawed, when the State was forced last year to transpose amended EU market transparency rules. That, itself, was two years after the EU handed down the laws.

It should never have taken so long.