Skip to content

Quest Diagnostics

Disclosed Dec 19, 201411 years agoConfirmed

Official notice

What is known

People affectedNot stated in the sources we have
DisclosedDec 19, 2014
HappenedNov 17, 2014
AttackNot stated
Data exposedNames, Social Security numbers
SectorHealthcare · US
StatusConfirmed

Sources

Source
California Attorney General breach notice: Quest Diagnosticsoag.ca.gov · Official notice
Maine Attorney General breach notice archive: Quest Diagnosticsmaine.gov · Official notice

Notices filed

WhereFiledPeople
California AGresidents of CADec 19, 2014
Maine AGresidents of MEDec 19, 20146
Maine AGresidents of MEAug 3, 20151

Other breaches at Quest Diagnostics

BreachAffected
Disclosed Oct 25, 2024Oct 25, 20241 year agoInsider1,062
Disclosed Nov 16, 2021Nov 16, 20214 years ago5,325
Billing vendor AMCA breach exposes data of 11.9 million Quest patientsJun 3, 20197 years agoVendor breach12M
Disclosed Dec 12, 2016Dec 12, 20169 years agoHacking34K
History of this record
  • 2026-09-25 · data_types: [] to ["names","ssn"] · backfill source
  • 2026-09-25 · added · backfill source

First seen 2026-09-25 (California AG), confirmed by California AG. Record counts are as reported. Not legal advice.

Everything about Quest Diagnostics

New breaches by email

Wednesdays, only in weeks with newly disclosed breaches, the largest first.

Double opt-in. Unsubscribe any time.