Quest Diagnostics
Disclosed Jun 3, 20197 years ago11,900,000 affectedConfirmed
Billing vendor AMCA breach exposes data of 11.9 million Quest patients
Quest Diagnostics said an unauthorized user had access to the web payment system of its collections vendor American Medical Collection Agency between August 2018 and March 2019, which held data on about 11.9 million Quest patients.
What is known
| People affected | 11,900,000 (as reported by the organization) |
|---|---|
| Disclosed | Jun 3, 2019 |
| Attack | Vendor breach |
| Data exposed | Names, Financial, Payment cards, Health, Social Security numbers |
| Sector | Healthcare · US |
| Status | Confirmed |
Sources
| Source | |
|---|---|
| Quest Diagnostics 8-K (June 3, 2019)sec.gov · SEC filing | SEC filing |
Notices filed
| Where | Filed | People |
|---|---|---|
| Researchtotal | Jun 3, 2019 | 11,900,000 |
Other breaches at Quest Diagnostics
| Breach | Affected | ||||
|---|---|---|---|---|---|
| Disclosed Oct 25, 2024Oct 25, 20241 year agoInsider | Oct 25, 20241 year ago | Insider | Healthcare | Confirmed | 1,062 |
| Disclosed Nov 16, 2021Nov 16, 20214 years ago | Nov 16, 20214 years ago | Not stated | Healthcare | Confirmed | 5,325 |
| Disclosed Dec 12, 2016Dec 12, 20169 years agoHacking | Dec 12, 20169 years ago | Hacking | Healthcare | Confirmed | 34K |
| Disclosed Dec 19, 2014Dec 19, 201411 years ago | Dec 19, 201411 years ago | Not stated | Healthcare | Confirmed | Unknown |
History of this record
- 2026-09-25 · added · seed source
First seen 2026-09-25 (Research), confirmed by Research. Record counts are as reported. Not legal advice.