GLOBALClaimed by RhysidaFirst sightinglinked via operator-confirmed · 100%
Posted to leak site Aug 24, 2023bd_ff39eb1c7fdf07a1
Prospect Medical Holdings
Clustered 7 filings across 6 jurisdictions · filing window Aug 24, 2023 → Sep 29, 2023. View entity profile → Other incidents for this victim →
incident inc_e1f9effd1cf5406d · merge_method deterministic · confidence 100%
Discovered → first regulatory filing
Range of discovered_at dates across filings
Gap between first leak claim and first regulatory filing
Time between earliest and latest filing
Not recorded for this incident
Materiality delta · SEC filing delay — no SEC 8-K in this cluster.
CA ME MT NH VT
Leak Site · HHS OCR · State AG
per-filing reported counts
State AGs report only their own residents; bars show per-filing counts.
Earliest sighting first · deep chronology in Litigation Timeline
Jul 31, 2023 → Aug 3, 2023
When the intrusion reportedly occurred, per the linked filings
Aug 1, 2023
Reported by NEW HAMPSHIRE AG, CALIFORNIA AG, VERMONT AG filings
Prospect Medical Holdings
Sep 13, 2023
Reported by MAINE AG filing
Prospect Medical Holdings, Inc. reported a ransomware incident affecting 1,309,096 individuals' PHI, including names, SSNs, DOBs, and medical data. The CE offered credit monitoring and implemented safeguards.
Affected (this filing):
About this clustering
DisclosureLens links filings into incidents through layered matchers: deterministic rules (same source document, multistate filings of one breach, tight-window same-victim pairs), a weighted-similarity scorer for cross-source candidates, and an operator review queue for everything uncertain. Each link records its own method and confidence — shown per filing in the timeline below. The system defaults to NOT merging when uncertain, because a false merge (collapsing two unrelated breaches) is more harmful than a false split (showing related filings separately); uncertain pairs route to human review instead of auto-merging. Filing summaries shown in the timeline are AI-generated extracts — verify each against its linked source.
Prospect Medical Holdings, Inc. notified the NH Attorney General of a data security incident. Unauthorized access occurred July 31-Aug 3, 2023. Discovered Aug 1, 2023. Employee and dependent PII (including SSNs) accessed. 73 NH residents affected. Notifications mailed Sept 29, 2023. Credit monitoring offered.
Affected (this filing): 73
Prospect Medical Holdings, Inc. reported an external system breach (hacking) occurring between July 31, 2023, and August 3, 2023, discovered on September 13, 2023. The incident affected 190,492 individuals nationwide, including 67 Maine residents. Acquired data included names and Social Security Numbers. The company provided written notification and offered one year of credit monitoring and identity theft protection services through IDX.
Affected (this filing): 190,492
Prospect Medical Holdings, Inc. notified Vermont AG that an unauthorized party accessed its IT network between July 31 and August 3, 2023, acquiring patient information including names and health data. The incident was discovered on August 1, 2023. The company engaged forensic investigators and offered one year of credit monitoring and identity protection services to affected individuals.
Prospect Medical Holdings, Inc. notified California residents of a data breach where an unauthorized party accessed IT network files between July 31 and August 3, 2023. The company discovered the incident on August 1, 2023. Affected data included names and Social Security numbers of employees, dependents, and patients. The company engaged forensic investigators, notified law enforcement, and offered one year of credit monitoring and identity protection services.
Prospect Medical Holdings, Inc reported a data breach to the Montana Attorney General. The breach was reported on 2023-09-29. The breach occurred from 7/31/2023 to 8/3/2023. 243 Montana residents were affected.
Affected (this filing): 243