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Costco

Disclosed Sep 22, 201511 years agoConfirmed

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

Source
Washington Attorney General breach notice: Costcoatg.wa.gov · Official notice

Notices filed

WhereFiledPeople
Washington AGresidents of WASep 22, 201529,425
History of this record
  • 2026-09-25 · added · backfill source

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

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