A recent study by Harvard professor Ben Edelman has uncovered a sneaky tactic by Google from its toolbar.

Google’s Toolbar acts as a gateway, for searchers, to a variety of Google software services. Of course, many of these services require a user to provide Google with information on the site that’s currently displayed in the browser and this is where the problem lies.

Edelman has discovered that the Google toolbar keeps tracking your browsing even after you disable that option.

Here is a rundown from his study:

In this article, I provide evidence calling into question the ability of users to disable Google Toolbar transmissions.

I begin by reviewing the contents of Google’s “Enhanced Features” transmissions. I then offer screenshot and video proof showing that even when users specifically instruct that the Google Toolbar be “disable[d]”, and even when the Google Toolbar seems to be disabled (e.g., because it disappears from view), Google Toolbar continues tracking users’ browsing.

I then revisit how Google Toolbar’s Enhanced Features get turned on in the first place – noting the striking ease of activating Enhanced Features, and the remarkable absence of a button or option to disable Enhanced Features once they are turned on. I criticize the fact that Google’s disclosures have worsened over time, and I conclude by identifying changes necessary to fulfill users’ expectations and protect users’ privacy.

Edelman used a network sniffer to see exactly how the toolbar sends data back to Google even though it has been disabled. There is a video screen cast here if you would like to see the experiment in detail.

So what has Google got to say for itself? A Google spokesperson tells us this has now been fixed:

To be clear, this is only an issue until a user restarts the browser, and it only affects the currently open tabs for a small number of users.

Specifically it affects those using Google Toolbar versions 6.3.911.1819 through 6.4.1311.42 in Internet Explorer, with enhanced features enabled, who chose to disable Toolbar without uninstalling it. Once the user restarts the browser, the issue is no longer present. A fix that doesn’t require a browser restart is now available on www.google.com/toolbar and in an automatic update to Google Toolbar that we are starting today.

This is an interesting find, especially in the wake of the latest privacy issues in China causing Google to consider pulling out. Although Google was quick to attack the Chinese government for abusing privacy rights, it seems they have a few privacy concerns of their own to resolve.