Every public data breach

Disclosed this week44On record26,355

44 disclosed this week · 26,355 on record

Costco

Disclosed Sep 22, 2015Confirmed

Official notice

What is known

People affectedNot stated in the sources we have
DisclosedSep 22, 2015
DiscoveredJul 17, 2015
HappenedJun 19, 2014
AttackHacking
Data exposedNot stated
SectorOther · US
StatusConfirmed

Sources

Official noticeatg.wa.gov
Washington Attorney General breach notice: Costco

Notices filed

Residents of WASep 22, 2015
Washington AG29,425 people
History of this record
Added2026-09-25
First recordedby backfillSource

First seen 2026-09-25 (Washington AG), confirmed by Washington AG. Record counts are as reported. Not legal advice.

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