A new privacy study says that Google-controlled web bugs are tracking users on 92 of the net's top 100 sites and about 88 per cent of almost 400,000 other domains.
Google Analytics was used by over 71 per cent of the domains, Google AdSense by over 35 per cent, and Google DoubleClick by over 26 per cent.
The study was conducted in March of this year. And preliminary numbers from April indicate that Google trackers appeared on roughly 80 per cent of 766,000 distinct domains on the net. The researchers call Google "the most dominant player in the tracking market."
Cookies for Microsoft's Atlas service, Redmond's DoubleClick competitor, appeared on 60 per cent of the top 100 websites (compared to DoubleClick's 70 per cent). But it turned up on less than 3 per cent of the nearly 400,000 total domains examined. Omniture and Quantcast cookies appeared on 57 per cent of the top 100 and less than 6 per cent of the 400,000.
The study does not imply that Google is combining data across its various tracking services. "We are not claiming that Google aggregates information from each of these trackers into a central database, though it does possess the capability to do so," the researchers write in their study, available here.
Speaking with the New York Times, Google took issue with that last bit. The company said that Analytics cookies are different for each site using the service, so it can't track users across multiple sites. And The Times has a Google managing counsel saying that contracts with customers don't allow the company to aggregate data from services like DoubleClick and AdSense.
Google did not respond to our requests for comment. But the DoubleClick-AdSense situation is at best a gray area. The two ad services are now using what would seem to be identical cookies, and to date, despite repeated questions, Google has not given us a direct answer on whether users are being tracked across both services.
If it's not tracking across both services, it would indeed be trivial for it to do so.
According to the Berkley study, only 36 of the top 50 websites acknowledged the use of third-party web bugs in their privacy policies, and all 36 stated that their policies did not cover third-party tracking. Meanwhile, some sites couldn't get their story straight.
What's more, the study says, 46 of the top 50 websites share data with their affiliates. And despite inquires sent to each site, it wasn't clear how many affiliates each site has. "Most stated that they do not disclose corporate information. Some companies did offer a little information... Based on our experience, it appears that users have no practical way of knowing with whom their data will be shared."
MySpace, the study points out, is owned by News Corp., which has over 1,500 subsidiaries. Bank of America has 2,300.
"The law on affiliate sharing generally is more permissive. Incentives for security and fair treatment of data are assumed to exist among affiliates," the study continues. "However, given the large size of affiliate networks, the fact that many affiliates are essentially unrelated entities with different business models in entirely different fields, and the practical challenge of identifying their size and scope, the more liberal treatment of affiliate sharing should be reexamined." ®