Independent public-records tracker. Not a government website.Facts from official state, HHS and SEC filings
BreachRecord

Largest data breaches of 2016

The 3 data breaches first reported in 2016 with the most people affected, using official totals from the filings. Where no official total was filed, the number is the sum of state filings and is labelled "At least". Facts come from official filings with US state attorneys general, the U.S. Department of Health and Human Services (HHS) and the SEC; each breach page links its sources.

Updated Oct 21, 2026 · Showing 1–3 of 3

# Organization First filed People affected Information exposed Filed with
1 Banner HealthBanner Health breach history 3,620,000Official total
  • Social Security number
  • Medical information
  • Date of birth
  • +2 more
 Washington AG, Maine AG, HHS, California AG
2 Yahoo Inc.Yahoo Inc. breach history At least 2,448,000Sum of state filings
  • Date of birth
  • Username and password
  • Name
  • +3 more
 Maine AG, California AG
3 21st Century Oncology21st Century Oncology breach history 2,213,597Official total
  • Social Security number
  • Medical information
  • Health insurance information
  • +1 more
 Washington AG, Maine AG, HHS, California AG

Other years

People affected is the official total from a filing, or “At least” the sum of state filings where no total was filed. Spotted an error? Report a correction.