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21st Century Oncology Data Breaches: History and Settlements

Last updated Oct 20, 2026 · 1 data breach in official filings

1 data breach involving 21st Century Oncology appears in official filings with US state attorneys general, the U.S. Department of Health and Human Services or the SEC. Each breach page lists the information involved, the agencies it was filed with and links to every official source.

Data breaches

  • 21st Century Oncology (March 2016) First filed Mar 4, 2016 · Filed with Washington AG, Maine AG, HHS, California AG
    2,213,597 people
    • Social Security number
    • Medical information
    • Health insurance information
    • +1 more

Sources

The facts for each breach come from the official filings listed in the Sources section of its page.

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