Cookies are small text files sent by a website to a visitor's computer. They are used mainly to allow a website to recognise a returning visitor. A cookie file defines its own lifespan and Google is changing its current policy of setting them to expire in 2038. Instead, Google cookies will be deleted two years after the user's last visit to Google, said global privacy counsel Peter Fleischer.
Google's privacy policies have come under scrutiny since it announced earlier this year that it would delete potentially identifying information in its search logs after 18 months.
That move provoked a storm of criticism about the fact that it and other firms even keep log identifiers that long. European privacy officials have asked Google to drastically reduce the amount of time it keeps those records.
Google has now moved to reduce the life of the cookies it sends to users' computers because, it said, it believes users are concerned about privacy.
"On the server side, we recently announced that we will anonymize our search server logs – including IP addresses and cookie ID numbers – after 18 months," said Fleischer in his official Google blog. "Now, we're asking the question about cookie lifetime: when should a cookie expire on your computer?
Google cookies will now expire two years after the user's last visit to Google. Though it may please privacy advocates, the ruling is unlikely to have a material effect on most users because usage of the site at any point in a two year period reactivates cookies. Most internet users use Google frequently.
The company said that the renewal part of the policy was designed to ensure that users do not 'lose' all their preferences every two years.
"Users who do not return to Google will have their cookies auto-expire after 2 years," said Fleischer. "Regular Google users will have their cookies auto-renew, so that their preferences are not lost."