Clustered 4 filings across 4 jurisdictions · filing window Oct 15, 2024 → Mar 17, 2025. View entity profile → Other incidents for this victim →
incident inc_9bbb0e234637405b · merge_method human · confidence 100%
Discovered → first regulatory filing
Gap between first leak claim and first regulatory filing
Time between earliest and latest filing
Not recorded for this incident
Discovery variance · Materiality delta · SEC filing delay — no SEC 8-K in this cluster; needs two dated filings.
CA MD MT
Leak Site · State AG
Earliest sighting first · deep chronology in Litigation Timeline
Oct 11, 2024
When the intrusion reportedly occurred, per the linked filings
Founded in 1927, Mark Thomas & Company have provided land surveying, engineering, urban design, and landscape architectural services that have set the stage for countless California roadways, structures, bicycle/pedestrian facilities, parks, communities, and flood control and utility systems. Mark Thomas is headquartered in San Jose, California.
Oct 19, 2024
Reported by CALIFORNIA AG 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.
Mark Thomas notified Maryland AG of a breach involving personal and health information of affected residents. The incident involved unauthorized access via compromised credentials. Mark Thomas is offering 12 months of credit monitoring and advising on fraud alerts.
Mark Thomas reported a data breach to the Montana Attorney General. The breach was reported on 2025-03-17. The breach occurred from 10/11/2024 to 10/19/2024. 2 Montana residents were affected.
Affected (this filing): 2
Mark Thomas notified the California Attorney General of a data security incident where an unauthorized actor accessed systems from October 11-19, 2024. The organization became aware of the potential unauthorized access on October 19, 2024. A forensic investigation and manual document review concluded on February 19, 2025, that personal information was included in the impacted data. The incident involved potential viewing and/or obtaining of files containing personal information. The organization engaged external cybersecurity professionals, secured systems, and is offering 12 months of complimentary credit monitoring to affected individuals.