BreachCensus

Yahoo! Inc.

United States of America

Yahoo! Inc. is an organisation in California. It appears on the California Attorney General breach-notification register and the Wisconsin DATCP data breach list with 3 confirmed incidents; the most recent notice was filed on December 14, 2016.

Data as of September 28, 2026.

Sources

Confirmed incident

US-CA

Disclosed
December 14, 2016

Timeline

  1. December 14, 2016
    Reported to regulator Regulator

    CA AG breach notification: an unknown number of California residents affected

    source

Litigation

  • Possible litigation — multiple candidate dockets found, not yet resolved to a single case.
What a California notice means

Governed by Cal. Civ. Code §1798.82. A copy of the notification must be sent to the Attorney General when a single breach requires notifying more than 500 California residents.

Note: no affected-count is published on this register.

California breach-notification register ↗

Confirmed incident

Filed in CA and WI

The same incident was filed separately with 2 jurisdictions within a few days of each other (CA and WI) — shown here as one incident.

Disclosed
September 22, 2016

Timeline

  1. September 22, 2016
    Reported to regulator Regulator

    CA AG breach notification: an unknown number of California residents affected

    source
  2. September 22, 2016
    Reported to regulator Regulator

    WI AG breach notification: an unknown number of Wisconsin residents affected

    source

Litigation

  • Possible litigation — multiple candidate dockets found, not yet resolved to a single case.
What a Wisconsin notice means

Governed by Wis. Stat. §134.98. No state agency must be notified. Affected individuals must be told within 45 days, and the national credit bureaus too when 1,000 or more people are notified; DATCP lists breaches reported to it or found to affect Wisconsin consumers.

Note: the count is Wisconsin residents only when published, not a total; many notices do not include one.

Wisconsin breach-notification register ↗

Confirmed incident

US-WI

Occurred
January 31, 2014
Disclosed
January 31, 2014

Timeline

  1. January 31, 2014
    Reported to regulator Regulator

    WI AG breach notification: an unknown number of Wisconsin residents affected

    source
  2. March 21, 2014
    Litigation filed Court

    RECAP docket 1:14-cv-02028 (ilnd): Johnson v. Yahoo! Inc.

    source

Litigation

Related

Disclosed around the same time