Google To Kill Third-Party Cookies In Chrome


Advertisers have relied on third-party tracking cookies for the last 25 years to track consumer behaviour online. Nearly all ad-tech platforms use cookies – whether it’s for targeting, retargeting or display advertising.

But this is soon changing.

Google has announced that they plan to phase out the support for third-party cookies in Chrome over the next two years, joining a growing list of browsers ditching the ubiquitous tracking technology.

Google’s plan to phase out third-party cookies in Chrome is part of a larger new initiative, known as Privacy Sandbox with open standards for tracking users while protecting their privacy.

Fundamentally, this move is to enhance privacy on the web. Users are demanding greater transparency, choice and control over how their data is used, which is why the web ecosystem needs to evolve to meet these increasing demands in making the web more private and secure for users.

The blocking of third-party cookies in Chrome is widely regarded as a fundamental change in online advertising. Given Google’s dominance in online advertising and that Chrome accounts for approximately 60% of the browser market share, Google’s decision to phase out third-party cookies in Chrome will have significant implications. It means discarding a mechanism that more or less sets the foundation for how personalised digital ads are delivered on the web.

Meanwhile publishers, agencies, ad-tech companies and brands are wondering what this will mean for the online advertising industry: “How will we track users? Can we survive on contextual targeting? How can we use our first-party data?”

Before we delve deeper, some basics.

What are Third-Party Cookies?

Cookies are text files with small pieces of data that are used to identify a user’s computer as they use a computer network. Third-party cookies are cookies that are set by a website other than the one the user is currently on. For example, a “Like” button on a website can store a cookie on visitor’s computer, which can later be accessed by Facebook to identify the visitor and see which websites he has visited.

Third-party cookie data allows marketers to learn about their users’ overall online behaviour, such as websites they frequently visit, purchases they’ve made and interests that they’ve shown on various websites. With this detailed data, marketers can build robust visitor profiles and create a retargeting list that can be used to display ads to.

What Google’s Privacy Sandbox Initiative Focuses on

According to Google, The Privacy Sandbox project’s mission is to “Create a thriving web ecosystem that is respectful of users and private by default.” The main mission is to end pervasive cross-site tracking through third-party cookies, which has become the norm on the web. Essentially, the underlying principle of the Privacy Sandbox is making user data anonymous, while still allowing advertisers to continue using behavioural targeting, without the pervasiveness associated with third-party cookies.

Privacy Sandbox’s main areas of focus include:

  • How to let websites collect user data from browser APIs that maintain the anonymity of individual users.
  • How to enable conversion measurements for advertisers without individual user tracking across the web.
  • How to serve ads to large groups of users without collecting identifying data from their browsers.
  • How to detect and prevent ad fraud, for example, bots, instead of real users, clicking on ads.

The End of Third-Party Cookies is Not the End of Tracking

Third-party cookies have been declining for over a decade. The first phase started in the mid-2000s when ad blockers were introduced. These browser plugins prevent ad-tech tags, like JavaScript snippets, from loading on a web page, in which case third-party cookies can’t be created.

Third-party cookies are not the only technology used today for tracking of users across the Internet. Other browsers like Safari and Firefox, which have been blocking third-party cookies since 2013, simply resort to workarounds. Facebook, for example, bypasses third-party cookies by using first-party cookies combined with a pixel tracker.

Some of the existing technologies that can track users just like third-party cookies include:

  • IndexedDB
  • Local Storage
  • Web SQL

Since the Privacy Sandbox project is in its infancy, no actual code currently exists for advertisers to test. However, there are several application programming interfaces (APIs) proposed to replace third-party cookies, one of which includes “Trust Tokens”.

The “Trust Token” API will allow developers to combat ad fraud by distinguishing the visitors that are bots and those that are real users, whilst verifying users without revealing their identity.

Another proposed process that Chrome’s Privacy Sandbox will use for remarketing is known as TURTLEDOVE (Two Uncorrelated Requests, Then Locally-Executed Decision On Victory). The interesting thing about this proposed approach is many of the key ad-decisioning and even auction mechanics will be conducted in the browser (on the user’s device) instead of by ad-tech platforms.

Google’s proposed alternatives will not be developed in a vacuum. Google Privacy Sandbox is an open standard, which means that everyone in the industry can give input and affect change. The World Wide Web Consortium has been working with Google on the development of the project, which is an indication that these standards could become consistent across browsers.

Consent is Poised to Take Centre Stage

Consent lies at the very heart of the most important data privacy law in the world, the EU’s General Data Protection Regulation (GDPR), and many other places around the world are following suit, like Brazil’s LGPD, Thailand’s PDPA, Singapore’s PDPA and South Africa’s POPIA.

The power to say “yes” or “no” to strangers who want to collect your personal data remains pivotal, which is why consent is poised to be more important than ever, integrating even closer and more seamlessly with the tracking technologies of tomorrow and the ad-tech industry itself.

In fact, consent is becoming so important that Google has taken a decisive turn with the launch of Google Consent Mode in September 2020. It enables websites to run all Google-services based on end-user consent.

Taking Advantage of First-Party Data

While third-party cookies are being phased out, first-party cookies that track basic data about your own website’s visitors are still safe, which means that first-party data that organisations gain from their website’s visitors will still remain intact.

Taking advantage of first-party data that you get when people intentionally engage with your brand is one of the ways to get around the absence third-party data.

Using email addresses or phone number as an ID is one of the ways a publisher can use their first-party data for identification. This involves a publisher asking users to create an account or provide an email address to access their content, for example to read a news article.

What Steps Should the Ad-Tech Industry Take?

With all that’s been happening in digital advertising over the past five years regarding privacy (the GDPR, etc.), it’s clear that the future of online advertising lies in privacy-friendly tech and processes.

This new update from Google is not something that should send marketers into a panic. Until Chrome shuts off third-party cookies, it will be business as usual. However, during the next two years advertisers will have to adapt and make some changes.

By planning for the future, participating in discussions around Chrome’s Privacy Sandbox, adapting their tech to make it privacy friendly, and staying abreast with new announcements, ad-tech companies will be well prepared for what lies ahead.

With all of the continual updates in online advertising, Signifi Media is taking the necessary actions to comply with the industry changes. We also have our own ad technology and in-house development team that will allow us to minimise the impact on our clients’ digital marketing. If you need expert advice and guidance in your online advertising during this transitioning phase, feel free to reach out to us.