The successful raid by hackers on Sony’s PlayStation Network is already being ranked among the biggest data thefts of all time. Here we count down some of the most significant previous security breaches.

5. T-Mobile insiders (2009) – the Information Commissioner revealed that corrupt T-Mobile employees had been raiding the firm’s database for customer details to sell to marketing firms.

4. HMRC lost CDs (2007) – the Labour government faced uncomfortable questions in Parliament and launched a full data security review after it emerged that HMRC had lost the entire child benefits database,containing records on 25 million Britons.

3. Heartland Payment Systems hack (2009) – hackers broke into this New Jersey payment processing firm to steal data from tens of millions of credit cards for sale on the black market. In 2009, Alberto Gonzalez was indicted as the ringleader of the gang.

2. Epsilon hack (2011) – earlier this year it emerged that the world’s largest email marketing firm had been breached by hackers, affecting the customers of major brands including Marks and Spencer.

1. TJX hack (2007) – hackers stole credit, debit and cheque data in this huge breach, as well as driving licence and social security information. More than 45 million people were affected by the attack, which was mounted via an insecure WiFi network.