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BayMark Health Services

Disclosed Jan 8, 20251 year ago265,701 affectedConfirmed

Official notice

Largest US addiction treatment provider notifies patients of data theft

BayMark Health Services said attackers accessed its systems between September 24 and October 14, 2024 and stole patient personal and treatment information; it learned of the incident on October 11, 2024 after an IT disruption.

What is known

People affected265,701 (as reported to HHS)
DisclosedJan 8, 2025
DiscoveredOct 11, 2024
HappenedSep 24, 2024
AttackHacking
Data exposedNames, Social Security numbers, Dates of birth, Health, Insurance, Government IDs
SectorHealthcare · US
StatusConfirmed

Sources

Notices filed

WhereFiledPeople
California AGresidents of CAJan 8, 2025
ResearchtotalJan 8, 2025
Vermont AGresidents of VTJan 8, 2025
HHS archivetotalJan 8, 2025265,701
California AGresidents of CAMay 2, 2025
Washington AGresidents of WAMay 2, 20252,263
Oregon DOJresidents of ORMay 2, 2025282,249
Vermont AGresidents of VTMay 2, 2025
Indiana AGresidents of INMay 2, 2025200
History of this record
  • 2026-09-25 · source: empty to https://ocrportal.hhs.gov/ocr/breach/breach_report.jsf · backfill source
  • 2026-09-25 · records_basis: organization to hhs · backfill source
  • 2026-09-25 · records: 16548 to 265701 · backfill source
  • 2026-09-25 · records_basis: empty to organization · backfill source
  • 2026-09-25 · records: empty to 16548 · backfill source
  • 2026-09-25 · source: empty to https://ago.vermont.gov/document/2025-01-08-baymark-health-services-data-breach-notice-consumers · backfill source
  • 2026-09-25 · source: empty to https://ago.vermont.gov/document/2025-05-02-baymark-health-services-data-breach-notice-consumers · backfill source
  • 2026-09-25 · attack: ransomware to hacking · seed source
  • 2026-09-25 · data_types: [] to ["names","ssn","dob","health","insurance","government-id"] · seed source
  • 2026-09-25 · summary: empty to BayMark Health Services said attackers accessed its systems between September 24 and October 14, 2024 and stole patient personal and treatment information; it learned of the incident on October 11, 2024 after an IT disruption. · seed source
  • 2026-09-25 · title: empty to Largest US addiction treatment provider notifies patients of data theft · seed source
  • 2026-09-25 · attack: unknown to ransomware · backfill source
  • 2026-09-25 · discovered: empty to 2024-10-11 · backfill source
  • 2026-09-25 · disclosed: 2025-05-02 to 2025-01-08 · backfill source
  • 2026-09-25 · added · backfill source

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

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