Privacy often comes at the expense of freedom of information. The two have a push-pull relationship with each other.

Today, the highest court in the EU came down hard on the side of privacy, ruling that Google must delete "inadequate, irrelevant or no longer relevant" in certain cases, when requested by a member of the public.

The decision is a blow to Google, and may also affect companies like Facebook and Twitter.

As The Guardian notes, the ruling means search engines such as Google will be classified as "data controllers" and are thus subject to data protection laws in EU countries. Instead of running a standard set of operations across the globe, as it has been doing, the Mountain View, Calif.-based company will need to field and respond to complaints from users in the EU about data that comes up in its search results, The New York Times reports.

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Google has argued that it does not control data; instead, it provides links to information already available on the internet.

But the EU court's decision holds the search engine accountable for information it links out to, noting that "without the search engine the information could not have been interconnected or could have been only with great difficulty." Therefore, in certain circumstances, the court said, Google is responsible for deleting links even "when its publication in itself on those pages is lawful."

So when can a person request to be "forgotten" by the search engine?

On that, the court is fairly vague, stating that in circumstances where data appears to be
"inadequate, irrelevant," or "excessive…in the light of the time that has elapsed" an individual may request that it be deleted “unless there are particular reasons, such as the role played by the data subject in public life, justifying a preponderant interest of the public.”

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What, exactly, qualifies as inadequate, irrelevant or excessive information remains to be determined, as does how long an individual must wait before asking Google to remove an offending link. The ruling also raises questions about the slippery relationship between the public's right to access information versus an individual's right to control his or her personal data.

"The principle that you have a right to be forgotten is a laudable one, but it was never intended to be a way for people to rewrite history," Emma Carr, acting director of the privacy rights campaign Big Brother Watch, told The Guardian. "Search engines do not host information and trying to get them to censor legal content from their results is the wrong approach. Information should be tackled at source…otherwise we start getting into very dangerous territory."

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