Microsoft accused Google of bypassing privacy protections in Internet Explorer, following accusations last week that Google was doing so in Apple's Safari browser.

When the IE team heard that Google had bypassed user privacy settings on Safari, we asked ourselves a simple question: is Google circumventing the privacy preferences of Internet Explorer users too? Dean Hachamovitch, corporate vice president of Internet Explorer, said in a blog post. We've discovered the answer is yes: Google is employing similar methods to get around the default privacy protections in IE and track IE users with cookies, he added.

In an earlier report, Google was accused of bypassing the privacy settings on Apple's Safari browser to track usage on iPhones and Macs without permission. Going by a report released by a Stanford University graduate student, Google has used a special computer code that tricks Apple's Safari Web-browsing software into letting them monitor many users. Jonathan Mayer, a graduate student and privacy researcher, wrote about Google's Safari tracking techniques in his blog post. Mayer's findings got wide attention after the Wall Street Journal featured it in a news story.

According to Microsoft, IE blocks third-party cookies unless the site includes a P3P Compact Policy Statement. Technically, Google utilizes a nuance in the P3P specification that has the effect of bypassing user preferences about cookies, Hachamovitch stated. Google sends a P3P policy that fails to inform the browser about Google's use of cookies and user information, he continued. P3P, or Platform for Privacy Preferences, is an official recommendation of the World Wide Web Consortium that sites use to summarize their privacy policies. However, the recommendation has been largely ignored since its introduction a decade ago.

Meanwhile, Google has said the report mischaracterizes the effort of the company. But the company admitted that a glitch accidentally allowed Google cookies to be set on Safari and promised a fix. Google has started removing the advertising cookies from Safari browsers, according to a statement by Rachel Whetstone, senior vice president of communications and public policy at the search giant.

Cookies are little bits of data about the Internet activity of users. They can be useful in instances such as remembering passwords and settings on sites that the user will be surfing on a regular basis. At the same time they also raise concerns about targeted advertising and how much data is really collected.