BreachCensus

Largest breaches

The 100 largest confirmed incidents on file, ranked by records affected. records_affected is always the TOTAL figure reported by the source document for that incident — a US state attorney general’s state-resident notification count is never used here, and is never summed into it. See Methodology for how the two figures are kept separate.

OrganizationRecords affectedDisclosedJurisdictionSource
Change Healthcare Inc.192,700,000October 14, 2025US-TXRegulator
Conduent Business Services, LLC (revised submission)62,486,662May 20, 2026US-TXRegulator
Conduent Business Services LLC62,224,658October 8, 2025US-NJRegulator
Aflac Incorporated22,653,844December 22, 2025US-TXRegulator
Cerner Corporation18,565,730July 25, 2025US-WARegulator
DentaQuest, LLC15,000,000July 16, 2026US-MARegulator
DentaQuest, LLC15,000,000July 16, 2026US-WARegulator
Aflac Incorporated (“Aflac”)13,924,906August 8, 2025US-GARegulator
Prosper Marketplace, Inc13,076,476December 10, 2025US-TXRegulator
Aesto, LLC9,540,683July 31, 2026US-ALRegulator
AssuranceAmerica Managing General Agency, LLC6,998,886June 17, 2026US-WARegulator
TriZetto Provider Solutions6,974,232February 6, 2026US-WARegulator
Episource, LLC6,725,572June 6, 2025US-CARegulator
Episource, LLC6,725,572June 6, 2025US-WARegulator
700Credit, LLC5,836,521December 16, 2025US-TXCourt
TransUnion LLC4,461,511September 4, 2025US-TXRegulator
Heights Finance Holdings Co.4,132,834August 14, 2026US-TXRegulator
Unlimited Technology Systems, LLC3,836,316July 21, 2026US-WARegulator
Medtronic Inc.3,834,294June 29, 2026US-WARegulator
Unlimited Technology Systems, LLC3,803,750July 21, 2026US-OHRegulator
CareCloud, Inc.3,756,469July 24, 2026US-NJRegulator
CareCloud, Inc.3,756,469August 18, 2026US-TXRegulator
University of Phoenix, Inc.3,489,274December 21, 2025US-WARegulator
TriZetto Provider Solutions3,433,965February 6, 2026US-MORegulator
Texas Parks and Wildlife3,187,000June 26, 2026US-TXRegulator
QualDerm Partners, LLC3,117,874February 22, 2026US-TNRegulator
QualDerm Partners, LLC3,117,874February 23, 2026US-WARegulator
Columbia University3,067,242August 7, 2025US-WARegulator
PIH Health, Inc.2,947,264January 31, 2025US-CARegulator
Baylor Genetics2,810,878August 18, 2026US-TXRegulator
Baylor Genetics2,810,878August 14, 2026US-TXRegulator
Navia Benefit Solutions, Inc.2,697,540March 18, 2026US-WARegulator
DaVita Inc.2,689,826August 1, 2025US-CORegulator
Veradigm LLC2,672,036September 22, 2025US-ILRegulator
Veradigm LLC2,672,036December 2, 2025US-WARegulator
Xsolis, Inc.2,523,302June 19, 2026US-WARegulator
Nacogdoches Memorial Hospital n2,507,073March 30, 2026US-TXRegulator
Navia Benefit Solutions, Inc.2,151,330March 18, 2026US-WARegulator
Insightin Health, Inc.1,949,534January 16, 2026US-MDRegulator
Anne Arundel Dermatology1,905,000July 11, 2025US-MDRegulator
Summit Pathology and Summit Pathology Laboratories, Inc.1,813,538October 18, 2024US-CORegulator
New York City Health and Hospitals Corporation1,800,000March 24, 2026US-NYRegulator
Insightin Health, Inc.1,777,141March 10, 2026US-TXRegulator
Kettering Adventist Healthcare1,695,382July 21, 2025US-OHCourt
Strategic Education Inc.1,513,518June 1, 2026US-WARegulator
Allianz Life Insurance Company of North America1,497,036July 25, 2025US-WARegulator
Radiology Associates of Richmond, Inc.1,419,091July 1, 2025US-VARegulator
Xsolis, Inc.1,396,519June 5, 2026US-TNRegulator
Everside Health1,389,758July 31, 2026US-WARegulator
PIH Health, Inc.1,369,533March 3, 2026US-TXRegulator
DermCare Management1,367,176April 10, 2026US-TXRegulator
DermCare Management1,361,735May 2, 2025US-FLRegulator
SimonMed Imaging1,275,669October 14, 2025US-TXRegulator
MCBS, LLC1,261,464June 26, 2026US-GARegulator
Absolute Dental Group, LLC1,223,635May 2, 2025US-NVRegulator
WestJet1,200,000October 3, 2025US-WARegulator
Southeast Series of Lockton Companies, LLC (Lockton)1,124,727February 28, 2025US-GARegulator
Farmers Insurance Exchange, Farmers Group, Inc. (its attorney-in fact), and their subsidiaries and affiliates1,071,300December 9, 2025US-TXRegulator
Community Health Center, Inc.1,060,936January 30, 2025US-CTRegulator
Frederick Health934,326March 28, 2025US-MDRegulator
Wilmer Cutler Pickering Hale and Dorr LLP911,658July 15, 2026US-WARegulator
ATSG, Inc909,469October 4, 2024US-NYRegulator
Texas Tech University Health Sciences Center El Paso815,000November 25, 2024US-TXRegulator
Texas Tech University Health Sciences Center813,892April 9, 2026US-WARegulator
Motility Software Solutions Inc766,670September 30, 2025US-WARegulator
McLaren Health Care743,131June 24, 2025US-MICourt
OpenLoop Health, Inc.716,000March 17, 2026US-IARegulator
Medusind Inc.701,475January 7, 2025US-FLCourt
People's Community Clinic700,000December 19, 2025US-TXRegulator
American First Finance LLC689,000September 12, 2025US-WARegulator
SitusAMC Holdings Corporation662,701February 20, 2026US-WARegulator
Texas Tech University Health Sciences Center650,000November 25, 2024US-TXRegulator
Quantum Health, Inc.625,945August 18, 2026US-TXRegulator
Erie Family Health Centers570,000March 27, 2026US-ILRegulator
AssetMark, Inc.570,000June 11, 2026US-WACourt
Kelly & Associates Insurance Group, Inc.553,332April 9, 2025US-MDRegulator
BAYADA Home Health Care, Inc.550,164July 21, 2026US-TXRegulator
Centers Lab NJ LLC542,377June 18, 2026US-NJRegulator
IMA Diligence Services, LLC525,306June 1, 2026US-TXCourt
Covenant Health, Inc.478,188January 5, 2026US-TXRegulator
Goshen Medical Center456,385September 18, 2025US-TXCourt
Allied Health MSO Holdco, LLC447,304August 25, 2026US-TXRegulator
The University of Pennsylvania442,500December 1, 2025US-WARegulator
Ascension Health437,329April 28, 2025US-MORegulator
Together Women's Health LLC (Aesto)416,262August 28, 2026US-TXRegulator
Philadelphia Corporation for Aging (PCA)410,491September 23, 2025US-PARegulator
Mercadien PC Certified Public Accountants402,741February 24, 2026US-TXRegulator
Monmouth University399,600August 21, 2026US-TXRegulator
Business or Organization Name* Cierant Corporation390,472March 12, 2026US-TXRegulator
Gulshan Management Services, Inc.377,082March 16, 2026US-TXCourt
Wakefield & Associates, LLC371,577November 12, 2025US-TXRegulator
Rocky Mountain Gastroenterology Associates PLLC366,491November 13, 2024US-COCourt
Northwest Radiologists, Inc./Mount Baker Imaging362,713October 28, 2025US-WARegulator
Networking Technology, Inc.353,844May 29, 2026US-NCRegulator
Lennar Mortgage, LLC348,416August 14, 2026US-WARegulator
Cookeville Regional Medical Center337,917April 17, 2026US-TXRegulator
ADT, Inc.331,536July 28, 2026US-WARegulator
Check City322,687March 19, 2026US-WARegulator
Monroe University320,973January 14, 2026US-TXRegulator
Ciox Health LLC, d/b/a Datavant Group320,702October 7, 2024US-AZRegulator