Those who object to their data being merged and used to target advertising have the choice not to use Google services, a company spokesman told ZDNet UK on Wednesday.
"We remain committed to data liberation, so if you want to take your information elsewhere you can," he added.
Google expects to see some negative reaction from users. "Our priority for this change is to give clear notice and choice to our users," the spokesman said. "We're also working hard to explain the benefits of this change to our users so they understand why they should continue using Google."
The company will not change how it shares data with advertisers, the spokesperson added, noting it does not sell personal information to advertisers.
"We're not changing how any personal information is shared outside of Google or the measures we take to protect information," said the spokesperson. "No users' settings regarding the sharing or visibility of their personal information are being changed."
"If you're signed in, we may combine information you've provided from one service with information from other services," said the post. "In short, we'll treat you as a single user across all our products, which will mean a simpler, more intuitive Google experience."
If you're signed in, we may combine information you've provided from one service with information from other services.– Google
For example, someone using an Android phone and Gmail could get reminders about calendar appointments based on location, said the post.
"We can provide reminders that you're going to be late for a meeting based on your location, your calendar and an understanding of what the traffic is like that day," said the post. "Or ensure that our spelling suggestions, even for your friends' names, are accurate because you've typed them before."
"From a privacy perspective this is unacceptable," said campaigner Alex Hanff. "People signed up under old privacy policies, and generally had no idea Google would integrate identity across services. We need to look at how regulatory pressure can be brought to bear to prevent this."
Google users must be informed about the use of targeted advertising, UK data protection authority the Information Commissioner's Office (ICO) told ZDNet UK on Wednesday.
"While it can prove useful to some service users, it is important that technology companies, such as Google, are aware of the privacy concerns that exist when behavioural advertising is used to target particular content at individuals," said the ICO. "Failure to inform users about changes may not only lead to a loss of trust in the company, but could also mean that they are failing to comply with the requirements of the Data Protection Act."
Google chief executive Larry Page signalled the company's direction in a conference call in October 2011. Page said that the Google+ social network would ultimately make the Google experience "magical".
"This means baking identity and sharing into all of our products, so that we build a real relationship with our users," said Page.
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