BreachCensus

Ascension Health

healthcareHealthcareUnited States of America

Ascension Health is a healthcare organisation in United States of America. It appears on the HHS OCR breach portal, the Massachusetts Attorney General breach-notification register, the California Attorney General breach-notification register and the Washington State Attorney General breach-notification register with 2 confirmed incidents; the most recent notice was filed on April 28, 2025.

Data as of September 1, 2026.

Sources

Confirmed incident

Filed in MO and MA — Hacking/IT Incident

The same incident was filed separately with 2 jurisdictions within a few days of each other (MO and MA) — shown here as one incident.

Disclosed
April 28, 2025
Records affected
437,329

Was I affected? →

Timeline

  1. April 28, 2025
    Reported to regulator Regulator

    MA AG breach notification: 96 Massachusetts residents affected

    source
  2. April 28, 2025
    Reported to regulator Regulator

    HHS OCR breach portal listing: Hacking/IT Incident; Network Server

    source

Litigation

  • Possible litigation — multiple candidate dockets found, not yet resolved to a single case.
What a Massachusetts notice means

Required under M.G.L. c. 93H. Notice to the Attorney General is required for a breach affecting any number of Massachusetts residents' personal information -- the statute sets no minimum count.

Note: the count is Massachusetts residents only, not a total.

Massachusetts breach-notification register ↗

Confirmed incident

Filed in WA, CA and MA — Ransomware Attack

The same incident was filed separately with 3 jurisdictions within a few days of each other (WA, CA and MA) — shown here as one incident.

Occurred
February 29, 2024
Disclosed
December 19, 2024

Timeline

  1. December 19, 2024
    Reported to regulator Regulator

    CA AG breach notification: an unknown number of California residents affected

    source
  2. December 19, 2024
    Reported to regulator Regulator

    WA AG breach notification: 5,787 Washington residents affected

    source
  3. December 19, 2024
    Reported to regulator Regulator

    MA AG breach notification: 2,632 Massachusetts residents affected

    source
  4. February 3, 2025
    Reported to regulator Regulator

    CA AG breach notification: an unknown number of California residents affected

    source
What a Washington notice means

Required under RCW 19.255.010. Notice to the Attorney General is required when a breach affects more than 500 Washington residents.

Note: the count is Washington residents only, not a total.

Washington breach-notification register ↗

What a California notice means

Required under Cal. Civ. Code §1798.82. A copy of the notification must be sent to the Attorney General when a single breach requires notifying more than 500 California residents.

Note: no affected-count is published on this register.

California breach-notification register ↗

Related

Same sector and location

Disclosed around the same time