DisclosureLens
HackingTelecom & MediaInformationStolen CredentialsData ExfiltratedCustomer Data InvolvedDelayed DiscoveryGovernment IDIdentity (basic)CriticalContained

T-MOBILE USA, INC.

bd_4f029ec65fed3c95 · schema v1 · pii pii-v1

Severity

Critical

Discovered

Aug 17, 2021

Filed

Aug 31, 2021

To disclose

14 days

Affected

647,980state residents only

Linked

7 filings

Confidence

69%
Full breach record for T-MOBILE USA, INC.22 incidents on file

T-Mobile USA, Inc. reported a cybersecurity incident in South Carolina affecting legacy Sprint and T-Mobile customers. Unauthorized access occurred on or before July 19, 2021, and was discovered on August 17, 2021. Personal data accessed included names, phone numbers, dates of birth, driver's license IDs, and Social Security numbers. No financial or payment card data was compromised. T-Mobile engaged forensic experts and federal law enforcement, offering two years of free identity protection.

South Carolina clock SC CRA notice due14 days 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 · 29 days
discovery → filing · 14 days

Jul 19, 2021

Begins

Aug 17, 2021

Discovered

Aug 31, 2021

Filed

This filing is one of 7 about the same incident.View merged incident

Linked disclosures

Why this link?

Regulatory filings (6) · sorted by filing gap

Show 2 more filingsup to 12d gap

Filing propagation · 7 filings · 7 states

View merged incident ↗
New Hampshire State AGAug 19 · first
Delaware State AGAug 19 · first
South Carolina State AG+12d · this page

Pattern: first filing Aug 19 (NH), last Aug 31 (SC) — a 12-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.