HackingProfessional ServicesProfessional ServicesCustomer Data InvolvedIdentity (basic)Financial accountMediumContained

Mercadien, P.C., CPAs

bd_bb8b76494cae40c6 · schema v1 · pii pii-v1

Severity

Medium

Discovered

Nov 7, 2025

Filed

Feb 23, 2026

To disclose

15 weeks

Affected

1,376state residents only

Linked

12 filings

Confidence

68%

Mercadien, P.C., CPAs, a South Carolina accounting firm, disclosed a data incident affecting personal information (names and financial account numbers) of individuals whose data was held by the firm. Unauthorized access occurred between September 17, 2025, and October 9, 2025, and was discovered on November 7, 2025. The firm engaged forensic experts, notified law enforcement, and provided 12 months of free credit monitoring.

J jump to incidentP pin to compareR raw source

South Carolina clock✓ SC CRA notice due15 weeks discovery → filing

⚠ unattributedNo provenance was recorded for this discovery date and it matches no other date on the record. It may be correct, but it is not independently grounded.

Incident timeline

undetected · 51 days

discovery → filing · 15 weeks / 108 days

Sep 17, 2025

Begins

Nov 7, 2025

Discovered

Feb 23, 2026

Filed

vs. sector median

4 wks faster

This filing is one of 12 filings about the same incident.View merged incident

Linked disclosures

Why this link?

Regulatory filings (10) · sorted by filing gap

Texas State AGbd_7b787e3dbbd82d8e2026-02-24 · +1dVerified
Indiana State AGbd_5a136d8dad7a13462026-02-17 · +6dVerified
Nebraska State AGbd_9581ab095364e27d2026-02-17 · +6dVerified
Delaware State AGbd_b06b2f75cc90e4452026-02-17 · +6dVerified

Show 6 more filings ↓up to 232d gap

New Hampshire State AGbd_6a472f77725ed7622026-01-05 · +49dVerified
Maine State AGbd_be4f63906a17f7282025-12-31 · +54dCandidate
New Hampshire State AGbd_aea05dfcc088a1bf2026-07-20 · +147dVerified
California State AGbd_3c090c1ae9c357382026-10-12 · +231dVerified
Oregon State AGbd_9073a5be3f931a412026-10-12 · +231dVerified
Texas State AGbd_cc54cf6a9eb2d0c22026-10-13 · +232dVerified

Showing first 10 of 11 linked disclosures.

Name: Mercadien, P.C., CPAs
norm: mercadien

Name: Mercadien, P.C., CPAs
norm: mercadien
Industry: Professional Servicesllm

Discovered: Nov 7, 2025
Breach occurred: Sep 17, 2025 – Oct 9, 2025
Undetected for: 51 daysoccurrence → discovery
Materiality determined: —
Notification sent: Feb 17, 2026
Affected individuals: 1,376state-resident count only
Data types: Identity (basic)Financial account
Attack vector: Unauthorized Access
MITRE ATT&CK: T1190 Exploit Public-Facing Application
Threat actor: External
Initial access: exploit_public_facing

During the incident: Engaged third-party forensic experts to assist in investigating what happened and what information may have been impacted
Notified law enforcement
Changes made: Provided access to free credit monitoring through Epiq - Privacy Solutions ID, for 12 months
Source: Quoted from the filing itself, not independently verified.

Time to disclose: 15 weeks(108 days from discovery to filing)
Compliance flags: SC CRA notice due
Discovery-date grounding: unattributedNo provenance was recorded for this discovery date and it matches no other date on the record. It may be correct, but it is not independently grounded.

Status: No extraction artifact recorded for this disclosure.

Filing propagation · 11 filings · 9 states

View merged incident ↗

Maine State AGDec 31 · first

New Hampshire State AG+5d

Indiana State AG+48d

Nebraska State AG+48d

Delaware State AG+48d

South Carolina State AG+54d · this page

Texas State AG+55d

New Hampshire State AG+201d

California State AG+285d

Oregon State AG+285d

Texas State AG+286d

Pattern: first filing Dec 31 (ME), last Oct 13 (TX) — a 286-day rolling notification. Rolling spreads often mean counsel is filing as thresholds trip per state. Why this link?

Cascade drawn from the first 10 linked disclosures of 11 — the full spread may be wider.

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://consumer.sc.gov/sites/consumer/files/Documents/Security%20Breach%20Notices/2026/Consumer%20Letter%20-%20Mercadien%20PC.pdf
DisclosureLens links to the originating regulator URL — full filing bodies are not redistributed from public surfaces (§4.5).
Filed at: Feb 23, 2026
Raw hash: 4256f691d3fd2690cc299307dac778680c6c53ca5196a60cdb7d110e66706708

Linked disclosures

Regulatory filings (10) · sorted by filing gap

Reporting entityMercadien, P.C., CPAs

Victim entityMercadien, P.C., CPAs

Incidentdiscovered Nov 7, 2025

Stated responseEngaged third-party forensic experts to assist in investigating what happened and what information may have been impacted

ComplianceSC CRA notice due

Extraction provenanceno artifact recorded

Source provenanceconsumer.sc.gov