Google Discloses Ad Bug Served Sensitive Ads
Court filings reveal a software error in Google's ad platform persisted for nearly three years before being fixed.
Updated on Nov. 6, 2026 in Advertising
Google filed court papers disclosing a software bug that served sensitive ads to some users. The error, inadvertently introduced in July 2019, was fixed by May 23, 2022, and Google argues there is no evidence it affected any plaintiffs in the privacy suit.
Why it matters
The disclosure bears on a pending privacy lawsuit in federal court and raises questions about how sensitive ad targeting is controlled in large-scale ad systems. Plaintiffs' counsel has also asked the presiding judge to reconsider a dismissed claim.
The bug ran for nearly three years, from July 2019 until Google personnel fixed it by May 23, 2022. It affected only Display serving where Optimized Targeting or Custom Segments were combined with a restricted advertisement, while Website Visitors remarketing, Google Analytics remarketing, and Similar Segments were unaffected.
The players
Google is the search and advertising company whose ad platform contained the bug and which is defending the privacy lawsuit.
Judge Vince Chhabria
Judge Vince Chhabria is the federal judge in the Northern District of California presiding over the privacy case and ruling on the dismissed claims.
The details
Google's Ads Safety Targeting and Trust & Safety teams uncovered the bug during a joint Personalized Ads PVI exercise in April 2022. In certain corner cases, targeted ads for a personal injury law firm were shown to users, according to the filing.
Timeline
July 2019: Software error inadvertently introduced into Google's ad platform.
April 2022: Bug discovered during a joint Personalized Ads PVI exercise.
May 23, 2022: Google personnel fixed the bug.
June 2025: Judge Chhabria allowed some claims to proceed and dismissed another.
December 3: Judge Vince Chhabria is expected to hold a hearing in the case.
Industry Dynamics
The disclosure extends a pattern of targeting-related privacy claims litigated in the Northern District of California against Google's advertising business. Because the bug affected only certain Display serving combinations, it underscores how narrow configuration interactions can produce outcomes that courts must examine.
Users of Google's ad products may be served sensitive ads only in narrow targeting combinations, which the company says it has corrected. The case may affect how advertisers can combine Optimized Targeting and Custom Segments with restricted advertisements.
The takeaway
Advertisers and users alike should recognize that narrow configuration interactions in ad systems can produce sensitive-ad exposure that persists unnoticed for years. Watching how the December 3 hearing treats the disclosed bug may clarify what accountability standards courts apply to such errors.
What happens next
Judge Vince Chhabria is expected to hold a hearing in the case on December 3.
Further reading
For more on how ad targeting is shaped by industry rules, see the Advertising section.
Source note: This article includes information reported by MediaPost.
