The Japanese giant has already suffered a huge dent to its credibility over the security breach, which saw details of millions of users compromised.
The firm has apologised profusely for the problem, but the UK Information Commissioner's Office believes that it the attack "could have been prevented if the software had been up-to-date, while technical developments also meant passwords were not secure"
Quarter of a million
The Office has issued Sony with a huge fine of £250,000 - or around $400,000.
"If you are responsible for so many payment card details and log-in details then keeping that personal data secure has to be your priority," said David Smith, Deputy Commissioner and Director of Data Protection.
"In this case that just didn't happen, and when the database was targeted – albeit in a determined criminal attack – the security measures in place were simply not good enough.
"There's no disguising that this is a business that should have known better. It is a company that trades on its technical expertise, and there's no doubt in my mind that they had access to both the technical knowledge and the resources to keep this information safe.
"The penalty we've issued today is clearly substantial, but we make no apologies for that. The case is one of the most serious ever reported to us. It directly affected a huge number of consumers, and at the very least put them at risk of identity theft."
Sony has, of course, made significant efforts to ensure that there will not be a repeat of the hack, but corporations will be mindful of the decision, given the growing desire to capture and hold user information.
Interestingly, a lawsuit brought in the US over the issue was thrown out by a judge, who said "there is no such thing as perfect security."
UPDATE: Sony has indicated that is will appeal the ruling, telling the BBC that it 'strongly disagrees' with the ICO's findings.
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Patrick Goss is the ex-Editor in Chief of TechRadar. Patrick was a passionate and experienced journalist, and he has been lucky enough to work on some of the finest online properties on the planet, building audiences everywhere and establishing himself at the forefront of digital content. After a long stint as the boss at TechRadar, Patrick has now moved on to a role with Apple, where he is the Managing Editor for the App Store in the UK.