John Muir Health - Walnut Creek Medical Center

John Muir Health - Walnut Creek Medical Center notified California AG on Apr 13, 2023 of a data breach, which occurred between Jul 1, 2021 and Mar 24, 2023.

Organization: John Muir Health - Walnut Creek Medical Center
Source: California AG · source record
Date reported: Apr 13, 2023
Date(s) of breach: 07/01/2021, 03/24/2023
Residents affected: Not published by this source
Data exposed: Not stated in the source listing
Notice letter: Not available
First seen by BreachTally: 2026-10-30 15:59 UTC

Dates and counts as filed by the organization with the agency. The breach window and the report date often differ by months.

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