MultiCare Health System

Disclosed Jul 25, 20224 years ago23,712 affectedConfirmed

Official notice

What is known

People affected	23,712 (as reported by the organization)
Disclosed	Jul 25, 2022
Discovered	Jun 2, 2022
Happened	May 18, 2022
Attack	Ransomware
Data exposed	Not stated
Sector	Healthcare · US
Status	Confirmed

Sources

Source	Kind
Washington Attorney General breach notice: MultiCare Health Systematg.wa.gov · Official notice	Official notice
Indiana Attorney General 2022 data breach report: MultiCare Health Systemin.gov · Official notice	Official notice

Notices filed

Where	Filed	People
Washington AGresidents of WA	Jul 25, 2022	22,679
Indiana AGresidents of IN	Oct 25, 2022	4

Other breaches at MultiCare Health System

Breach	Disclosed	Attack	Sector	Status	Affected
Disclosed Aug 21, 2020Aug 21, 20206 years agoRansomware	Aug 21, 20206 years ago	Ransomware	Healthcare	Confirmed	179K
Disclosed Jan 26, 2017Jan 26, 20179 years agoHacking	Jan 26, 20179 years ago	Hacking	Healthcare	Confirmed	1,249

History of this record

2026-09-25 · records_basis: empty to organization · backfill source
2026-09-25 · records: empty to 23712 · backfill source
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.

Everything about MultiCare Health System

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