Privacy rules created under the EU's Electronic Communications Framework should be extended to cover online banking, video games, shopping and social media, Viviane Reding said in a speech.
Current rules, which are being implemented in the UK as part of amendments to the Privacy and Electronic Communications Regulations, require telecommunications companies and internet service providers to notify their customers and national regulators of personal data breaches immediately.
"I think it is important that users are notified if someone has unlawful access to their data," Reding said. "It is essential for consumer confidence that they know what happens to their data.
Reding said that in the upcoming review of data protection laws in Europe she would investigate the extension of the data breach notification process to more than just telecoms companies.
Addressing German privacy experts, including Germany's Data Protection Commissioner Peter Schaar, at a discussion in Brussels, Reding expressed her concern at a "veritable wave" of data security incidents over the last two weeks.
Her comments came shortly after Sony apologised for a security breach involving 77 million PlayStation Network account holders, and a week after Apple said that it would update the software that logs the location of users of its mobile devices.
She spoke of five cornerstones to solid data protection laws to restore consumer confidence: the right to be forgotten, data transparency, corporate responsibility, independent data monitoring systems and 'privacy by design' – ensuring that data protection safeguards are built into information systems from the start.
In her speech, Reding said that she could understand if Apple and Sony had eroded "the trust of our citizens" in technology in the face of the high-profile data security lapses.
This trust had to be reinstated, she said, through good legislation, independent data protection authorities and responsible company policy.
She stressed the importance of letting customers know immediately when their personal data had been put at risk. "Seven days is much too long," she said, referring to the delay between when Sony's security breach occurred - between April 17 and 19 - and when the company notified its customers on April 26.
She urged that new EU data protection laws must be "clear and legible" and meet "current and likely future challenges" to the fundamental right to privacy.
"A social network with more than 200 million users in the EU must stick to EU law, even if it is based in the US and its data is stored in a so-called cloud," she said.
"European citizens care deeply about protecting their privacy and data protection rights," she added in a later statement to the International Herald Tribune.
"Any company operating in the EU market or in any online product that is targeted at EU consumers should comply with EU rules."
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