/ Technology

Who’s watching you online? Find out with Collusion

It was a bright cold day in April and the clocks were striking thirteen. But the year’s 2012, not 1984, and, as the time flickers on your PC screen, the world’s advertisers are waiting to see which website you’ll visit next.

Ok, maybe not the world’s advertisers, but enough of them to make a difference to your experience of online.

Internet advertising is already big business. And although many advertisers still use the strategy of ‘if you throw enough mud at the wall, some of it will stick’, they can also track which websites you’re visiting, build a profile of your interests and target you with bespoke ads tailored to your tastes.

Is anything private online?

None of this is new. Google’s long been gathering data about you, and Twitter recently sold two years’ worth of tweets to Datasift, a data firm that will mine the content and sell any useful information to advertisers.

And after recently updating its privacy policy, Google can now join up the information it collects about you from all its various services, whether it’s your searches or emails. All meaning that online ads that feel eerily relevant usually aren’t there by coincidence.

But just as speed guns and speed gun detectors (and speed gun detector detectors…) became embroiled in a seemingly infinite regress, so too may the watcher-versus-the-watched of online monitoring.

Mozilla’s Collusion Firefox add-on

Mozilla is developing an add-on for its Firefox web browser that shows which advertising networks are watching as you browse the internet. ‘Collusion’ records the sites you’ve visited and lets you know of any others that knew you were there. On-screen arrows then show you the companies who are getting information about you, where they’re getting it from and whether they’re sharing this data between them.

Collusion’s still in development and so not 100% accurate, but it gives a taste of what’s going on behind-the-scenes while we unwittingly click away.

Yet, does it really matter if other companies are watching you, and does knowing that they are have any impact on what you do online? We’re all familiar with online ads and are happy to ignore them, so will making them more relevant really change anything? I suppose if you know about them tracking you, you can opt-out – but is this as easy to do as it should be?

How the data’s used will be key to all this. If weak emotional states or personal tragedies are detected in emails and exploited by predatory marketers, that would add an uncomfortable dimension.

But might targeted ads actually enrich our online experience by providing content that’s relevant to us? Perhaps this is a small price to pay for an otherwise transaction-free service; the flip side of not having to pay for Google is that you become a marketable product in your own right and carry a price on your head…


one example of how websites work to our detriment;

You visit a website and search for/view a product.
The information about what you searched for is saved – whether you buy it or not
When the search/views reach a certain number (set by the business) it flags up and the price is increased.

Over simplified, but true.
Insurance, holidays, energy, loans, mortgages, phones, food shopping, etc, etc.
Hence the push towards everything being “online” or having to register an email or join a facebook group or “re tweet” a post.
Regulation is dictated by “business need” and is due to be extended further still by information sharing with government, looking for business opportunities, etc.

Sounds petty, but it effects the prices that everyone has to pay and until those in power (of what ever colour) get a grip, it will only continue.

Michael P says:
10 July 2017

Now it’s July 2017 and the comment holds true now as it did in 2012. However, isn’t it the same in the real world? After interest or demand rises to a certain level, the price goes up?
What is objectionable is the cancerous growth of the net, e.g. by “liking” something, unless you are very careful, this is passed on to all and sundry.


Michael- time and technology has moved on vastly what was said here then has mostly been superseded by just about every website/third party/ Google/ etc that exists on the web. What made you “safe ” then does not do so now and this must be clearly stated so that no one reading this convo is left under any illusions as to the current postilion . You are tracked “to death ” now in many very sophisticated ways and if anybody disagrees with me (and I hope they do ) I would love to list EVERY hidden tracker of every description but the list is vast and can be highly technical. Thats why I have a whole range of different types of blockers but that wont stop your ISP ,s server from collecting data on you unless you change that to . Even built in programmes in Windows 10 track you and the hidden ones CANT be turned off , the list is endless ! As for Do Not Track that is now classed as a ploy to make you feel safe , apart from the fact its voluntary – they might , I say might stop targeting you with specialised ads BUT -quote will STILL -Collect and Store and Monetise your data -end quote . I just wish I could start a convo on all the devious things big business get up to on the web to make money out of you ,it would make the Big Boys unhappy but it might the general public very happy.

elfsn says:
20 March 2012

I like the Don not track add-on of firefox. This add-on is developed by firefox and now can be used in other browsers too. I have installed it in my chrome, of course firefox and Avant browser.These are the three browsers I use.
One add-on is enough I think.If I didn’t install Do not track,I would try Collusion.


Hi elfsn, Katie might be able to correct me if I’m wrong – I believe Collusion is a visual tool to show you all the different companies/ad networks that know where you are, and showing their connections between them. Whereas ‘Do not track’ is a tool to actually stop them tracking you.

Harry says:
20 March 2012

I think perhaps Which should start by setting its own example, by eliminating some of the unnecessary third parties it is allowing to see its visitors.

On this page alone, firefox noscript is currently blocking scripts for:


It is perfectly possible for a company to host a forum on its own servers, which means there is no necessity to leak information to third parties. None of these third party sites are needed at all.


Hello Harry and thanks for the response. We do talk about some of these scripts in our cookie policy https://conversation.which.co.uk/our-cookie-policy/

Google-analytics.com provides us with data about how many people visit our website, addthis.com controls the ‘Share this’ buttons at the bottom of this post. googleapis.com makes much of the website work. And then the rest of those listed relate to the social sharing buttons at the left of every Conversation – Twitter, Facebook, Reddit and Google+, all run by ‘sharethis.com’. These are explained in our FAQ under the section ‘Sharing and Social networks’ https://conversation.which.co.uk/frequently-asked-questions/

You can choose to use these buttons to share our content or not and we’re also happy for you to opt-out of using cookies using the number of options out there, as again explained in our cookie policy. We like to be as upfront about these as possible and will look at putting these explanations in our cookie and/or privacy policy, rather than just in our FAQ. Thanks, Patrick.


This surveillance is generally wasted in my case because, although I notice that there are annoying adverts on the page I am looking at, I do not usually notice which companies are advertising. Nevertheless, I am aware that following a visit to certain sites [M&S is one, and insurance companies also figure], the next time I go to a certain newspaper website my peripheral vision catches sight of those names in the pop-ups, banners and ads that fall across the screen as the page loads. The first time I thought it was a coincidence but it’s obviously a well-organised marketing ploy. Still wasted though – I never buy on impulse.