Microsoft has announced plans to give its customers greater control over the search information it stores on their online behaviour.

Under the terms of its new privacy policy, Microsoft said its search query data will become anonymous after 18 months by permanently deleting cookie IDs, which remind users of their search preferences.

The software giant said that it will also give customers more control over the search information it collects and let its users decline advertisements targeted to their web surfing choices.

“We have been thinking deeply about privacy related to search and online advertising and believe it’s crucial to evolve our principles,” said Peter Cullen, chief privacy strategist at Microsoft.

The announcement comes just a week after Google revealed plans to change the way the company uses cookies.

Under the terms of its new privacy policy the internet giant said that its cookies will now automatically delete after two years. However, critics slammed the plans, because the cookies will only expire if the user doesn’t visit the Google website again in that time period.

Microsoft also revealed that it will join together with to call on the industry to develop global privacy principles for data collection, use and protection related to searching and online advertising. The companies hope to encourage dialogue between industry bodies and provide an update on their progress in September.

"Anonymous user data can be very useful to enhance search products for all users, but people should have access to privacy controls based on their level of comfort around the storage of their search data," said Doug Leeds, vice president of product management at