Google updated its privacy policy this summer, letting Google combine personal info from Gmail and other tools with DoubleClick browsing data to target ads
When Google bought the advertising network DoubleClick in 2007, Google founder Sergey Brin said that privacy would be the company's … Tweets: @kashhill Tweets: Kashmir Hill / @kashhill : Google quietly dropped its longstanding wall between anonymous online ad tracking and user's names. http://www.propublica.org/...
Context & Ripple Effects
When Google bought DoubleClick in 2007, Sergey Brin promised privacy protections would come with it, and for nearly a decade the company kept a wall between anonymous ad-tracking cookies and named account holders. ProPublica's reporting on the quiet summer policy change shows that wall is gone: DoubleClick browsing histories can now be joined with personal information from Gmail and other signed-in Google products.
That makes Google's ad inventory name-addressable at scale, a capability rivals built around but Google had publicly forsworn — which is why the change was made via a terms-of-service edit rather than an announcement.
First-order effects
- Advertisers buying through DoubleClick can now target ads using a person's actual identity rather than an anonymized cookie, immediately raising the value of Google's ad inventory against non-logged-in networks.
- Users who assumed their browsing was tracked only pseudonymously are now profiled by name across Google properties, with no action required beyond having a Gmail account and not opting out.
Second-order effects
- Competing ad networks and publishers face pricing pressure to offer comparable logged-in targeting of their own, accelerating the industry-wide race to link browsing behavior to real identities.
- User backlash pushes Google into a decade-long retrofit of control surfaces — from the refreshed Ad Settings and Why this ad? tools in 2018 to changes that later let users disable targeted ads without breaking other features — transparency added after the data combination was already standard practice.
Third-order effects
- If the pattern holds, permission boundaries eroded quietly get rebuilt only as disclosure tools rather than data limits — the same structure behind the 2025 finding that Google's own Display & Video 360 platform allowed targeting of Americans' sensitive data despite internal rules against it.
- Regulators and privacy litigants gain a template case: a written commitment made at acquisition (Brin's 2007 pledge) contradicted by a silent policy edit becomes the kind of documented pivot that shapes future consent and merger-condition enforcement.
The trend: Google's ad business is progressively dissolving the line between anonymous behavioral tracking and identified users, then managing the fallout with post-hoc transparency tools rather than reversing the data combination itself.