BayMark Health Services

Disclosed Jan 8, 2025265,701 affectedConfirmed

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 affected	265,701 (as reported to HHS)
Disclosed	Jan 8, 2025
Discovered	Oct 11, 2024
Happened	Sep 24, 2024
Attack	Hacking
Data exposed	NamesSocial Security numbersDates of birthHealthInsuranceGovernment IDs
Sector	Healthcare · US
Status	Confirmed

Sources

Official noticeoag.ca.gov

California Attorney General breach notice: BayMark Health Services

Official noticeatg.wa.gov

Washington Attorney General breach notice: BayMark Health Services

Official noticejustice.oregon.gov

Oregon DOJ breach notice: BayMark Health Services

The organizationbaymark.com

BayMark notice of data privacy incident

Newsbleepingcomputer.com

Largest US addiction treatment provider notifies patients of data breach

Official noticeago.vermont.gov

Vermont Attorney General: 2025-05-02 BayMark Health Services Data Breach Notice to Consumers

Official noticeago.vermont.gov

Vermont Attorney General: 2025-01-08 BayMark Health Services Data Breach Notice to Consumers

Official noticein.gov

Indiana Attorney General 2025 data breach report: BayMark Health Services

Official noticeocrportal.hhs.gov

HHS OCR breach report (archive, resolved): BayMark Health Services (Business Associate, TX)

Notices filed

Residents of CAJan 8, 2025

California AGCount not stated

TotalJan 8, 2025

ResearchCount not stated

Residents of VTJan 8, 2025

Vermont AGCount not stated

TotalJan 8, 2025

HHS archive265,701 people

Residents of CAMay 2, 2025

California AGCount not stated

Residents of WAMay 2, 2025

Washington AG2,263 people

Residents of ORMay 2, 2025

Oregon DOJ282,249 people

Residents of VTMay 2, 2025

Vermont AGCount not stated

Residents of INMay 2, 2025

Indiana AG200 people

History of this record

source2026-09-25

empty to https://ocrportal.hhs.gov/ocr/breach/breach_report.jsfby backfillSource

records_basis2026-09-25

organization to hhsby backfillSource

records2026-09-25

16548 to 265701by backfillSource

records_basis2026-09-25

empty to organizationby backfillSource

records2026-09-25

empty to 16548by backfillSource

source2026-09-25

empty to https://ago.vermont.gov/document/2025-01-08-baymark-health-services-data-breach-notice-consumersby backfillSource

source2026-09-25

empty to https://ago.vermont.gov/document/2025-05-02-baymark-health-services-data-breach-notice-consumersby backfillSource

attack2026-09-25

ransomware to hackingby seedSource

data_types2026-09-25

[] to ["names","ssn","dob","health","insurance","government-id"]by seedSource

summary2026-09-25

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.by seedSource

title2026-09-25

empty to Largest US addiction treatment provider notifies patients of data theftby seedSource

attack2026-09-25

unknown to ransomwareby backfillSource

discovered2026-09-25

empty to 2024-10-11by backfillSource

disclosed2026-09-25

2025-05-02 to 2025-01-08by backfillSource

Added2026-09-25

First recordedby backfillSource

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

Everything about BayMark Health Services