Breach filing
ArchivedTrinity Health: 46,526 individuals, Mar 2023.
Trinity Health reported a breach of unsecured protected health information to the HHS Office for Civil Rights on 6 March 2023. The filing records the organisation as a business associate in Michigan and lists 46,526 individuals affected, which makes it the 40th largest of the 238 Michigan filings on the register and the 213th largest of the 746 filings submitted nationally in 2023. Among the 18 Michigan filings made in 2023 it ranks 7th.
Individuals affected
46,526
As reported to HHS
Modelled cost (IBM 2025)
$7.44M
Method shown, not disclosed
Rank in MI
40th
of 238 Michigan filings
Rank in 2023
213th
of 746 filings nationally
Section F.1 / The filing
As posted by HHS OCR
Every value below is the portal's own field for this filing, plus its rank within the register.
- Covered entity type
- Business Associate
- Individuals affected
- 46,526
- Breach submission date
- 6 March 2023
- Submission year
- 2023
- Type of breach
- Hacking/IT Incident
- Location of breached information
- Business associate present
- Yes
- State
- Michigan (MI)
- Portal status
- listed in the HHS OCR breach portal archive
- Rank in Michigan by size
- 40th of 238
- Rank in 2023 nationally
- 213th of 746
- Michigan median filing
- 3,754 individuals
- Register id (derived)
- MI-20230306-trinity-health
Section F.2 / In context
Where this filing sits in Michigan and in 2023
OCR classifies the incident as a hacking or IT incident, with the breached information held in email. Hacking/IT Incident is the type recorded on 148 of the 238 Michigan filings (62%) and on 82% of all filings submitted in 2023. Email appears on 29% of Michigan filings.
A business associate is recorded as present on the filing, as it is on 30% of Michigan filings. At 46,526 individuals the breach is 12 times the Michigan median filing of 3,754 and 12 times the national median of 4,000 across all 7,884 filings. It sits in the 10,000 to 99,999 band, which holds 1,938 filings.
As of 28 August 2026 the case is listed in the HHS OCR breach portal archive. OCR's closing summary of the case is reproduced in full below.
Michigan's breach notification statute (MCL 445.72) requires notice to affected residents without unreasonable delay. Its attorney general threshold: not currently required (pending SB 360 would require it at 100+ residents). The HIPAA Breach Notification Rule ran alongside it: notice to affected individuals and to HHS without unreasonable delay and no later than 60 days after discovery, which is the clock that put this filing on the portal.
Multiplying 46,526 individuals by IBM's $160 customer-PII cost per record (Cost of a Data Breach 2025, the figure the site's calculator uses) gives a modelled $7.44M; the 2026 edition's $192 gives $8.93M. Both are modelled estimates with the method shown, not costs disclosed by Trinity Health. For scale, IBM's 2026 average cost of a healthcare breach is $6.64M, so this filing models at 1.3 times the sector average.
Section F.3 / OCR closing summary
The portal's archived description, in full
Written by the Office for Civil Rights when the case was closed and reproduced verbatim from the HHS export.
Trinity Health, the business associate (BA), reported that an employee was the target of an email phishing scheme that compromised the protected health information (PHI) of 46,526 individuals. The PHI involved included names, addresses, dates of birth, financial information, medications, and other treatment information. Trinity notified HHS, affected individuals, and the media. In its mitigation efforts, the BA strengthened its access controls and retrained its workforce.
Section F.5 / Modelled cost
46,526 individuals through IBM's per-record figures
Modelled cost / method shown, not a disclosed cost
ModelledIBM 2025 customer PII, $160 per record
$7.44M
46,526 x $160
IBM 2026 customer PII, $192 per record
$8.93M
46,526 x $192
Method: individuals affected, as reported by Trinity Health to HHS, multiplied by IBM's customer-PII cost per record (Cost of a Data Breach 2025 Figure 6 and the 2026 edition). No cost has been disclosed by the entity for this filing; the figure is a planning estimate, not a fact about the breach. IBM's per-record figures come from mid-volume breaches and IBM cautions against applying them to breaches involving millions of records; the site's per-record page explains where the multiplication holds and where it breaks down.
Context: IBM's average cost of a healthcare breach is $6.64M in the 2026 report ($7.42M in 2025); the global average across all sectors was $4.44M in 2025.
Cost per record: method and limits / Healthcare breach cost, IBM 2026
Section F.6 / Notification clock
Michigan statute and the HIPAA rule
State notification statute
Michigan: MCL 445.72
Identity Theft Protection Act
- Notice to individuals
- Without unreasonable delay
- Attorney general threshold
- Not currently required (pending SB 360 would require it at 100+ residents)
- Private right of action
- No: No PROA under the statute; other theories such as negligence may apply
- Penalty
- Up to $250 per failed notification, capped at $750,000 per breach event
The HIPAA Breach Notification Rule runs alongside the state statute: notice to affected individuals and to HHS without unreasonable delay and no later than 60 days after discovery.
Section F.7 / Peer filings
Michigan filings closest in size
Neighbours by size rank among Michigan filings in 2023, topped up from other years where 2023 has too few. Filings of 10,000 or more link to their own page.
| Covered entity | Type | Individuals | Submitted | Breach type | Location | BA |
|---|---|---|---|---|---|---|
| University of Michigan | Healthcare Provider | 61,033 | 23 Oct 2023 | |||
| Kent County Community Mental Health Authority d/b/a Network180 | Healthcare Provider | 59,334 | 22 Dec 2023 | |||
| Teijin Automotive Technologies Welfare Plan | Health Plan | 25,464 | 6 Feb 2023 | |||
| TGI Direct, Inc. | Business Associate | 16,113 | 21 Nov 2023 |
Index / Companion schedules
13 HHS breach register
→Hub: every filing, by state, year and entity.
04 Biggest breaches
→Mega-breaches with primary-source cost figures.
Industry / Healthcare
→IBM 2026: $6.64M average, 13 years at #1.
Regulation / HIPAA penalties
→OCR enforcement tiers and the 60-day rule.
11 50-state laws
→Deadline, AG threshold and penalties per state.
Cost / Per record
→Where the per-record model is reliable.
Provenance
Source: U.S. Department of Health and Human Services, Office for Civil Rights, Breach Portal (breaches affecting 500 or more individuals), retrieved 2026-08-28. Public domain. Individuals affected and dates as reported by the covered entity.
Portal: ocrportal.hhs.gov breach report. Statutory basis: HITECH Act section 13402(e)(4): the Secretary must post a list of breaches of unsecured protected health information affecting 500 or more individuals. Breaches affecting fewer than 500 individuals are reported to OCR annually and are not posted, so they are not on this register. Status wording follows the portal's two tabs ("Cases Currently Under Investigation" and "Archive") as of 28 August 2026; a filing moves to the archive when OCR closes the case. Modelled costs on this site are a method applied to the reported count, using IBM Cost of a Data Breach per-record figures, and are never a cost disclosed by the entity. This row: hhs-breach-archive__2026-08-28.csv, export row 1921.
Corrections: if you represent a listed entity and the portal row has been amended, email [email protected] with the portal entry and we will re-pull the export.