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Stanford Study Finds Personal Info Leaked To Online Advertisers

PALO ALTO (CBS SF) – A new Stanford study has found that dozens of the most popular websites on the Internet are sharing user's personal information with advertisers.

Stanford computer researchers looked at 185 of the most popular websites and found that over 60 percent of the time, those sites were sending user names and email addresses to third-party advertisers, seemingly without user consent.

KCBS' Matt Bigler Reports:

Among the websites studied were the Wall Street Journal, Home Depot, and Weather Underground.

For instance, when entering a wrong password on the Wall Street Journal's website, the user's email address was sent to 7 different companies, while clicking an ad on the Home Depot website was passed out to 13, and Weather Underground sent out emails to up to 22 companies.

The study did not say what the information was used for, but the Federal Trade Commission says the information may be used to track and customize advertising.

One of the researchers from the study recommends trying to use the built-in "Do Not Track" feature on several popular internet browsers like Safari or Firefox.

KCBS Technology Analyst Larry Magid said ad networks may be behind this leaking of personal information.

"These companies have lots of software that they embed in the ads," Magid said. "And apparently some of it can leak personal information. But the questions are, are they collecting it and what are they doing with it?"

Consumer watchdog groups are pointing to the Stanford study as reason for a "Do Not Track" law, which is also backed by the Federal Trade Commission.

Weather Underground said they "currently have our team resolving this issue."  Home Depot said it does not trade, sell or rent consumer information but is now researching the findings.

Home Depot's full statement:

"Just a few hours after we found out about this, we quickly made adjustments to limit the information we share with the vendors servicing our local ad program.

The Home Depot takes our customers' privacy seriously. We do not trade, rent or sell our customers' information. We may use the information we collect in accordance with our Privacy and Security Statement to improve our product and service offerings and to enhance and personalize our customers' shopping experiences. To that end, per our policy, we may share certain information with our service providers who help us accomplish these objectives."

Steve Holmes
Senior Manager
Corporate Communications
The Home Depot

Here are some helpful tools to protect your privacy online:
DoNotTrack.us
NetworkAdvertising Initiative
Digital Advertising Alliance

(Copyright 2011 by CBS San Francisco. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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