New EU fines will apply to 'old' data breaches

If the compromised personal information is sensitive, companies will need to inform their customers too.

Failure to do so may lead to a fine, which could be up to €10m or two percent of the company's annual turnover, whichever is higher.

A European Commission official confirmed on Monday (9 April) that data breaches that happened before 25 May, but are kept silent until after that, will also be liable for such a fine.

"If this behaviour [of keeping a data breach secret] would continue - even if it started a long time ago and continues - and is discovered after the GDPR comes into play, then it's relevant," said the source.

The official briefed journalists on Monday on a swathe of digital affairs, a day ahead of the EU's Digital Day in Brussels, on the condition of anonymity. He made his comments on the GDPR when asked about it by EUobserver.

"If you discover the crime the moment it happens, but it started a long time ago, this doesn't really matter. This is not retroactive application, this is application of the actual case," he noted.

The official stressed that the 25 May deadline has been public knowledge for over a year.

"If there is a breach discovered the day after, the GDPR will apply," he said.

"I hope that every company dealing with our personal data takes the May deadline very, very seriously," he added.

This means that for companies that still have a kept-secret data breach, it may merit to fess up before 25 May.

In two recent high-profile cases of data breaches, they were revealed by media reports. Last month, it was revealed that Facebook users' data had been shared with UK consulting firm Cambridge Analytica without those users' consent.

Last November, Uber was shown to have covered up for over a year personal information of 57 million of its users.