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Are you being tracked online?

Advertisers are most likely tracking you, sort of. Should you be concerned?

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This is Leo Notenboom for

This week there was news of a movement to create a “do not track” registry
for the internet, much like the “do not call” registry.

Yep, big brother may not be tracking you, but it’s likely that Madison
Avenue is.

Most people don’t realize how much their online activities are being tracked
by retailers and advertisers. Most don’t think about it, and those that do
typically have a serious and often paranoid misconception about exactly what’s

For example a retail store might place your customer number in a cookie on
your machine so that the next time you visit the site automatically receives
that cookie and knows who you are.

Advertisers can also place so-called “third party” cookies on your machine.
Since the same advertiser may be displaying ads on thousands of websites they
can track where you go across those sites, even the sites you’ve never been to

So here comes the paranoia: “Oh my God, you mean advertisers are tracking

Well, yes … but no.

They’re likely not interested in you as a specific individual.
There are simply too many people for them to bother tracking anyone
specifically. Advertisers are interested in crowds of people, and they collect
or “aggregate” the data to see what trends those crowds are following. For
example, if half of the people that visit Joe’s on-line book store also visit
Mary’s on-line grocer, that’s very interesting data that might be used to
tailor specific or more relevant offers to that crowd.

If you’re one of the people in that crowd … well, your identity is likely
just lost in the noise. does this kind of thing within their store all the time. They
track what you’ve purchased and even what you’ve just looked at, so as to make
suggestions of other merchandise that might appeal to you.

Most advertiser tracking is really not much more than the same thing, only
with less accuracy, applied to larger groups of people, and across a broader
range of sites. Sites may not know who you are, but they may be able to better
target what they offer you based on the characteristics of the kinds of crowds
you appear via tracking to belong to.

Yes, you can disable cookies, but then a bunch of sites stop working
completely. You can disable the third party cookies in most browsers if you
like, but there are apparently ways around this that allow the same kinds of
information to still be collected.

This isn’t to say we shouldn’t be watchful, we should. This type of tracking
data could be abused. That’s one reason I actually do business on-line with a
handful of companies that I trust.

But in the long run, with a little bit of common sense, I’m just not that

I’d love to hear what you think. Visit and enter 11964 in the go
to article number box to access the show notes, the transcript and to leave me
a comment. While you’re there, browse the hundreds of technical questions and
answers on the site.

Till next time, I’m Leo Notenboom, for

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14 comments on “Are you being tracked online?”

  1. While I’m not sure what you mean by ‘disabling’ cookies, I always go to Tools in Internet Explorer, then under Delete Browing History, I delete everything there that I can, including cookies. To date, I’ve haven’t found doing that kept any sites from working afterward. I’ve also deleted cookies with AVG Anti-Spyware with no problem afterward with nonworking sites. BombayGranny

  2. Tracking is simply not an issue for many. I run Firefox with the Adblock Plus and Permit Cookies add-ons. I rarely see online ads and all cookies from most sites are immediately removed when the browser session is closed. Further, my IP address is dynamically assigned by my ISP, changing each time my DSL modem logs in, making tracking difficult by IP address.

    What I’d like to know, are there any viable alternatives to push advertising?

  3. Deleting all cookies deletes some that are useful, such as saved logon names so you don’t have to enter them every time.

    A better way is to use Karen Kenworthy’s ( free Cookie Viewer. Scan the list of cookies and delete any that you don’t want. Any cookies that look like tracking cookies add it to the blocked cookies list in Internet Explorer/Tools/Internet Options/Privacy/Sites. So that site can never again put a cookie on your computer.

  4. I no longer allow CCleaner or other programs to clean out cookies. As long as everything is working OK it is just too much bother to start all over every month putting in my information in order to get another cookie. They are more useful than most users realize.

  5. I am currently not concerned with tracking, however it has been revealed that that government tracks personal phone calls and other private matters in the USA. With the co-operation of the ISPs, this can become a dangerous practice.

  6. Leo, you stated “…but there are apparently ways around this that allow the same kinds of information to still be collected.” What are the techniques used? Or what do you think they are using?

    Hash: SHA1

    I’ve only heard it as a passing reference, but what I heard had to do with
    advertiser-specific subdomains off of the parent domain. So something like would still be allowed to place and fetch cookied information
    if you allow As I said, my understanding is incomplete here.


    Version: GnuPG v1.4.7 (MingW32)


    Hash: SHA1

    Nope. The browsers keep separate cookie collections.


    Version: GnuPG v1.4.7 (MingW32)


  9. I went into Explorer/Tools/Internet Options/Privacy/Sites and found a lot of advertisers listed in the “blocked” box, several of them are in Cookies, so that means blocking these cookies is not working! I can’t get rid of ad.yieldmanager, it keeps coming back. I went in Internet Options and blocked third party cookies and with first party cookies checked the “prompt” box. Now, I am getting so many messages asking me if I want to allow a Cookie, I check the “block” option and it takes clicking on that 3 or 4 times before the message disappears….

  10. I am horrified to see that an unpublished court record of a case that was dismissed, and that I was part of years ago and withdrew from has been published for all to see when my name is searched. Most of the other claimants are not. I was not even the originator of the case. Who put this infomation under my name? Why am I being tracked? How can I have this removed? This is not done to child molesters. Can you Google their name and it says CHILD MOLESTER? I think not. Is there something I can do about this? It is as if this is something personal against me and the internet is furnishing a voice against the powerless. HELP!

  11. I believe ‘trackmenot’ add on doesn’t work.Gzapper 1.45 may,but to get to most sites you need to ‘restore the cookie’.As google wants to track you.Vidalia/tor/privoxy does work,but to write comments on Mininova,you need to restore the cookie’as they ban you ‘masked’ IP address.Most other IP hiders DO NOT work.’Ninjaproxy’ is ok,but an ad box may keep coming up,and it leaves some history in index.dat analyzer.

  12. AnalogX Cookiewall is good,when IE or Mozilla and other cookie culling software lets some slip through,so you must delete any new entries caught within it.

  13. There is some tracking going on. A while ago I had a problem with HP printer, and I contacted support. We emailed back and forth on one email address only(aol). Low and behold they sent the customer survey to a totally different email address which had not been use. This email address is on Gmail. Another email letter I get on a regular basis has now started to send their ads to this Gmail account thought the Gmail account is very dormant. When I contacted them they just said that I could opt out. The two email address used have the same address on the pre part of the address line.


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