🍁Vermont State AGlinked via multistate filing link · 100%
Clustered 5 filings across 5 jurisdictions · filed Dec 21, 2023. View entity profile → Other incidents for this victim →
incident inc_c65226d9ceba42c2 · merge_method deterministic · confidence 100%
Discovered → first regulatory filing
Range of discovered_at dates across filings
Time between earliest and latest filing
Not recorded for this incident
Leak precedence · Materiality delta · SEC filing delay — no leak-site claim in this cluster.
CA FEDERAL MT NH VT
SEC 8-K · State AG
Earliest sighting first · deep chronology in Litigation Timeline
Apr 11, 2023 → Apr 12, 2023
When the intrusion reportedly occurred, per the linked filings
Apr 12, 2023
Reported by VERMONT AG, NEW HAMPSHIRE AG, CALIFORNIA AG filings
Middlefield Banc Corp. disclosed via Item 8.01 8-K that its subsidiary, The Middlefield Banking Company, suffered an April 2023 cyber-attack that disrupted computer systems. A forensic review determined that nonpublic information of current/former employees, customers and others was obtained, potentially including names, SSNs, driver's license info, dates of birth, financial account information, medical information, passport numbers, payment card info, and usernames/passwords. The Bank is notifying impacted individuals and offering complimentary identity protection services.
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.
The Middlefield Banking Company experienced a data security incident on or about April 12, 2023. An unauthorized actor accessed systems and acquired files containing names and account numbers of employees and customers between April 11-12, 2023. The bank notified affected individuals on December 21, 2023, offering 12 months of credit monitoring. Federal law enforcement was notified.
Middlefield Banking Company reported a data breach to the Montana Attorney General. The breach was reported on 2023-12-21. The breach occurred from 4/11/2023 to 4/12/2023. 33 Montana residents were affected.
Affected (this filing): 33
Middlefield Banking Company experienced a data security incident between April 11-12, 2023, where an unauthorized actor accessed systems and acquired files containing employee and customer information. The bank notified federal law enforcement, implemented enhanced security controls, and provided credit monitoring services to affected individuals. 54 New Hampshire residents were notified.
Affected (this filing): 54
The Middlefield Banking Company experienced a data security incident on April 12, 2023, where an unauthorized actor accessed systems between April 11-12, 2023. The actor acquired files containing names, dates of birth, and passport numbers of employees and customers. The bank engaged outside specialists, notified federal law enforcement, and implemented enhanced security controls. Affected individuals were offered 12 months of credit monitoring.