Google Chrome to Phase Out Third-Party Cookies in Two Years

In a January 14, 2020 blog post published by Justin Schuh, the Director of Chrome Engineering, Google announced its intention to phase out third-party cookies from the Google Chrome browser within the next two years.

Cookies are small pieces of information saved by the web browser and used by websites to track user’s certain actions and behaviors. They can be used to customize the browsing experience, make website interactions more efficient (by, for example, remembering items in the shopping cart), or deliver targeted advertisements.

Third-party cookies are created by websites other than the website the user is visiting and are used for cross-site tracking, retargeting, and ad-serving.  When the user visits a website that uses scripts from an advertising network, that network sets a cookie in the user’s browser.  When the user visits another website that uses tracking scripts from the same network, the ad network checks the value of the cookie and knows that the user visited both websites.  Third-party cookies and related technology have created a serious privacy concern for users who don’t want to be tracked on-line without their consent.

Two other major browsers, Mozilla’s Firefox and Apple’s Safari, already block third-party cookies by default.  Google, however, decided to take a more measured approach as, according to Google, “by undermining the business model of many ad-supported websites, blunt approaches to cookies encourage the use of opaque techniques such as fingerprinting (an invasive workaround to replace cookies), which can actually reduce user privacy and control.”

Thus, Google plans to phase out the third-party cookies over the next two years, while simultaneously developing an ad tech “privacy sandbox” where websites are able to gather some information but eventually hit a wall where the browser cuts them off.  Furthermore, Google will limit insecure cross-tracking starting in February of 2020, by treating cookies that don’t include a SameSite label as first-party only, and require cookies labeled for third-party to be accessed over a secure HTTPS protocol.

The forthcoming demise of third-party cookies will continue to drive new privacy-conscious ad tech technologies such as “privacy sandbox” and contextual targeting. Meanwhile, if your browser continues to support third-party cookies, you might disable them now in the browser setting.