Doubleclick is a business owned by Google that makes it money from online advertisers and publishers. This is done by:
Online publishers use Doubleclick to display adverts on their websites.
Doubleclick will let advertisers control how often an ad is shown to a browser, how long it
is shown for and how often it will appear.
This comes in two categories:
Targeting for one website owner: An online publisher can set a Doubleclick cookie to tell them what sections of their sites you are browsing. Doubleclick will then judge the type of adverts you might like to see from what you’re browsing. For example, if you are on a news website and you visit the sports pages, then adverts for match tickets may be more relevant than makeup. This information belongs to the website owner only.
Targeting in advertising networks: Google runs a service called Adsense, in which lots of different publishers pool the information they get on browsers. This helps them build up a better idea of the type of adverts someone might want to see. This is a third-party advertising cookie.
Who uses Doubleclick?
Any web publishers can use Doubleclick, as long as they meet the company’s terms and conditions. Google also uses Doubleclick across its own sites.
What information is Doubleclick tracking?
This tells Doubleclick the time and date you saw an advert. It also shows:
userid: the unique ID number the cookie has given your browser
ad_id: the unique ID of the advert
ad_placement_id: the ID of where the advert was seen on the site
referral_url: what page you were on when you saw the advert
Because it records your IP address, Doubleclick can also make a good guess of your country and town/city, too.
How is this information used?
On its own, this data can tell Doubleclick how many times you have seen an ad and, for example, whether you need to see the UK or US version. It cannot find out any personal information about you.
If the cookie is set on an website that is part of AdSense and then you browse another site using AdSense, the the same information will be recorded and pooled. Over time, guesses can be made about the interests of the person using that browser – whether they like football or ballet, for example, or if they visit Marks & Spencers more than Tesco..
If enough browsers display similar patterns, they become part of a “segment” labelled something like “football lovers”, “fine food lovers”, “current affairs enthusiasts”, etc – these become labels that Doubleclick lets advertisers choose from when they select the types of people they want to see their ads.
Once Doubleclick have an idea about the interests of the person using the browser, they will try to use them to infer how old you are and whether you are male or female (again, to put you in a segment).
To check what segments Doubleclick has you in, go to Google’s ad preferences manager (you don’t have to be signed in to Google).
Even if Doubleclick is used to serve adverts, Google says there are some websites where segments won’t be created: for example, health websites (where there is a risk of building up a profile of a medical condition) and political websites (where they might build up a picture of a political affiliation).
How much money does Doubleclick make?
Google bought DoubleClick for $3.1bn in 2008; since then its financials are combined with other parts of Google.
Google currently generates 96% of its revenue through its advertising products.
In 2011, it saw advertising revenues of $36.5bn, with $10.4bn coming from non-Google sites in its ad network.
Is the data sold to third parties?
Google says it is not sold to third parties. When the service is being used by a publisher for its own purposes (not in an ad network), the publisher owns that data, not Doubleclick.
If data has not been sold on, has it been given to or shared free of charge with third parties?
Not directly. However, the Doubleclick platform is a charged-for product and the use of segments is part of the appeal for advertisers. While they are never given information about individual browsers, they do benefit from all the data in an aggregated form.
How long is the data stored for on the user’s browser and on Doubleclick’s servers?
Doubleclick cookies on the browser are set to expire after a number of years (we have seen dates in 2014 for these). However, the override for this is clearing cookies.
Newer cookies “60 days in market” and “30 days in market” are actually more valuable to advertisers as they give a better indication of what the person using that browser is interested in right now.
IP addresses are anonymised after nine months and the data in cookies is anonymised after 18 months. At this point they are not used.
What evidence is there that Doubleclick deletes the data?
A tricky question to answer, but when it comes to the cookie on your browser, Google says if you opt out from receiving Doubleclick cookies and visit its ad preferences manager, it will recognise your opt-out status.
Is the data ever matched to personally identifiable information?
Never, says Google. This would be a breach of Doubleclick’s terms and conditions. The information obtained from the cookies is also never combined with information that Google obtains from its other products and services. You browsing behaviour will never be linked to your Gmail account, for example.
What other ways does it track?
In addition to its Doubleclick cookies, Google says that if you click on an advert a cookie will be set on your browser. This is designed so that the company that advertised will know if you then, after seeing an advert, went on to buy the product.
Do the cookies circumvent privacy-enhancing software?
No special effort is put into circumnavigating tools that are designed to block cookies from working, says Google.
Can Google give one example of how tracking genuinely benefits the people being tracked?
The case from Google
• Relevancy (Before cookies the web was much worse at distributing adverts that had absolutely no relevance or interest to the people browsing. It still isn’t an exact science but they say it’s hard to argue with the evidence that ads that use targeting are more likely to be clicked on.)
• Frequency capping (Cookies can control how often a browser sees the same advert, so browsers don’t get pushed the same advert continuously.)
• Control (Unlike other forms of tracking, such as digital fingerprinting, cookies provide ways for savvy web users to control and block particular advertisers.)
Long-term benefit: it helps pay for the content you read on the web.