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Marshfield Clinic Health System

Disclosed Nov 7, 202510 months ago35,952 affectedConfirmed

Official notice

What is known

People affected35,952 (as reported to HHS)
DisclosedNov 7, 2025
AttackHacking
Data exposedNames, Health
SectorHealthcare · US
StatusConfirmed

Sources

Source
HHS OCR breach report: Marshfield Clinic Health System (Healthcare Provider, WI)ocrportal.hhs.gov · Official notice

Notices filed

WhereFiledPeople
HHS OCRtotalNov 7, 202535,952
History of this record
  • 2026-09-25 · added · backfill source

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

Everything about Marshfield Clinic Health System

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