HackingProfessional ServicesProfessional ServicesCustomer Data InvolvedDelayed DiscoveryIdentity (basic)Government IDPHIHealth (basic)HighContained

Greylock McKinnon Associates

bd_c55a125d8e9e0f58 · schema v1 · pii pii-v1

Severity

High

Discovered

May 30, 2023

Filed

Apr 5, 2024

To disclose

44 weeks

Affected

13,674

Linked

10 filings

Confidence

64%

Full breach record for Greylock McKinnon Associates →4 incidents on file

Greylock McKinnon Associates, Inc. (GMA), a litigation support consulting firm, detected a cyberattack on May 30, 2023, involving unauthorized access to personal and Medicare information. The incident affected approximately 13,674 individuals, including residents of California, Texas, Puerto Rico, and Rhode Island. Affected data included names, dates of birth, addresses, Medicare Health Insurance Claim Numbers (containing SSNs), and medical/health insurance information. GMA engaged third-party cybersecurity specialists, notified law enforcement and the DOJ, and deleted the affected DOJ data. The company is offering 24 months of credit monitoring and fraud assistance to affected individuals.

J jump to incidentP pin to compareR raw source

California clockDiscovered May 30, 2023 → Notified Apr 8, 2024314d ✗ CA 60-day late44 weeks discovery → filing

Incident timeline

discovery → filing · 44 weeks / 311 days

May 30, 2023

Begins

May 30, 2023

Discovered

Apr 5, 2024

Filed

vs. sector median

+27 wks slower

This filing is one of 10 about the same incident.View merged incident

Linked disclosures

Why this link?

Regulatory filings (9) · sorted by filing gap

South Carolina State AGbd_4f59e4feb1207f512024-04-05Verified
Maine State AGbd_524d78fcdff1e19d2024-04-05Verified
Oregon State AGbd_ba7fccfadfcbb07d2024-04-05Verified by operator
New Hampshire State AGbd_8b7ba321f28889a02024-04-04 · +1dVerified

Show 5 more filings ↓up to 42d gap

Washington State AGbd_862de986dcc37c522024-04-16 · +11dVerified
Montana State AGbd_08e358e2c4d44d732024-02-23 · +42dCandidate
New Hampshire State AGbd_8b8abd614469d3d92024-02-23 · +42dVerified
Maine State AGbd_e0ca51cf3adad76c2024-02-23 · +42dVerified
Indiana State AGbd_ebe27468fd5864a12024-02-23 · +42dVerified

Name: Greylock McKinnon Associates
norm: greylock mckinnon associates
Domain: gma-us.com

Name: Greylock McKinnon Associates
norm: greylock mckinnon associates
Domain: gma-us.com
Industry: Professional Servicesllm

Discovered: May 30, 2023
Breach occurred: May 30, 2023
Undetected for: 0 daysoccurrence → discovery
Materiality determined: —
Notification sent: Apr 8, 2024
Affected individuals: 13,674nationwide
Data types: Identity (basic)Government IDPHIHealth (basic)
Data elements: Social Security numberDate of birthMedical information
Attack vector: Unauthorized Access
MITRE ATT&CK: T1078 Valid Accounts
Threat actor: External
Regulator citations: Notified the U.S. Department of Justice (DOJ)Notified law enforcement

During the incident: Detected unusual activity on our internal network
Promptly took steps to mitigate the incident
Consulted with third-party cybersecurity specialists to assist with our response
Notified law enforcement
Notified the DOJ
Deleted DOJ data from its systems after the incident
Changes made: Offering complimentary access to Single Bureau Credit Monitoring/Single Bureau Credit Report/Single Bureau Credit Score services for 24 months
Providing proactive fraud assistance through Cyberscout through Identity Force
Source: Quoted from the filing itself, not independently verified.

Time to disclose: 44 weeks(311 days from discovery to filing)
Compliance flags: CA 60-day late · 314d
Discovery-date grounding: letter-groundedThe discovery date is the detection date narrated in the notification letter — the defensible tier.
Clock breakdown: Statute Window Elapsed Threshold Status
California
Discovered: May 30, 2023
→ Notified: Apr 8, 2024
314d 60 days (analyst band, pre-2026 discoveries) CA 60-day late

Statute	Window	Elapsed	Threshold	Status
California	Discovered: May 30, 2023 → Notified: Apr 8, 2024	314d	60 days (analyst band, pre-2026 discoveries)	CA 60-day late

Status: No extraction artifact recorded for this disclosure.

Filing propagation · 10 filings · 8 states

View merged incident ↗

Montana State AGFeb 23 · first

New Hampshire State AGFeb 23 · first

Maine State AGFeb 23 · first

Indiana State AGFeb 23 · first

New Hampshire State AG+41d

South Carolina State AG+42d

Maine State AG+42d

Oregon State AG+42d

California State AG+42d · this page

Washington State AG+53d

Pattern: first filing Feb 23 (MT), last Apr 16 (WA) — a 53-day rolling notification. Rolling spreads often mean counsel is filing as thresholds trip per state. Why this link?

Evidence ladder

Leak-site claim

Attacker assertion only. Establishes: claim date, group, alleged victim.

Press / market report

Unlocks: incident narrative, operational impact. Still no compliance clock.

State AG / regulator filingThis record

Unlocks: discovery date, data types, affected count, compliance clock.

SEC 8-K / victim statement

Unlocks: materiality, stated response, full audit trail. Ceiling removed.

Source URL: https://oag.ca.gov/ecrime/databreach/reports/sb24-583540
DisclosureLens links to the originating regulator URL — full filing bodies are not redistributed from public surfaces (§4.5).
Filed at: Apr 5, 2024
Raw hash: e261002fb5c623af008657fd586b8de61e69607438e55854cc3b72de2921b34f

Linked disclosures

Regulatory filings (9) · sorted by filing gap

Reporting entityGreylock McKinnon Associates

Victim entityGreylock McKinnon Associates

Incidentdiscovered May 30, 2023

Stated responseDetected unusual activity on our internal network

ComplianceCA 60-day late

Extraction provenanceno artifact recorded

Source provenanceoag.ca.gov