Breach filing
ArchivedSiouxland Anesthesiology, Ltd.: 13,000 individuals, Jul 2015.
Siouxland Anesthesiology, Ltd. reported a breach of unsecured protected health information to the HHS Office for Civil Rights on 31 July 2015. The filing records the organisation as a healthcare provider in South Dakota and lists 13,000 individuals affected, which makes it the 3rd largest of the 15 South Dakota filings on the register and the 42nd largest of the 270 filings submitted nationally in 2015. Among the 3 South Dakota filings made in 2015 it ranks 1st.
Individuals affected
13,000
As reported to HHS
Modelled cost (IBM 2025)
$2.08M
Method shown, not disclosed
Rank in SD
3rd
of 15 South Dakota filings
Rank in 2015
42nd
of 270 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
- Healthcare Provider
- Individuals affected
- 13,000
- Breach submission date
- 31 July 2015
- Submission year
- 2015
- Type of breach
- Hacking/IT Incident
- Location of breached information
- Network Server
- Business associate present
- No
- State
- South Dakota (SD)
- Portal status
- listed in the HHS OCR breach portal archive
- Rank in South Dakota by size
- 3rd of 15
- Rank in 2015 nationally
- 42nd of 270
- South Dakota median filing
- 1,632 individuals
- Register id (derived)
- SD-20150731-siouxland-anesthesiology
Section F.2 / In context
Where this filing sits in South Dakota and in 2015
OCR classifies the incident as a hacking or IT incident, with the breached information held in a network server. Hacking/IT Incident is the type recorded on 8 of the 15 South Dakota filings (53%) and on 21% of all filings submitted in 2015. Network Server appears on 47% of South Dakota filings.
No business associate is recorded on the filing; 20% of South Dakota filings do involve one. At 13,000 individuals the breach is 8.0 times the South Dakota median filing of 1,632 and 3.3 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.
South Dakota's breach notification statute (S.D. Codified Laws 22-40-19 et seq.) requires notice to affected residents no later than 60 days from discovery or notification of the breach. Its attorney general threshold: more than 250 South Dakota 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 13,000 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 $2.08M; the 2026 edition's $192 gives $2.50M. Both are modelled estimates with the method shown, not costs disclosed by Siouxland Anesthesiology, Ltd.. For scale, IBM's 2026 average cost of a healthcare breach is $6.64M, so this filing models at 0.4 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.
Siouxland Anesthesiology, the covered entity (CE), reported it was the subject of a criminal malware attack. The CE reported that hackers infiltrated one of its computer servers and installed malware that left patients' electronic protected health information (ePHI) vulnerable to unauthorized access. The exposed ePHI included patients' names, addresses, dates of birth, and, in some cases, Social Security numbers. The breach affected approximately 13,000 individuals. Following the breach report to the individuals, media and HHS, the CE investigated the incident and provided affected individuals with credit monitoring information and contact information should they have questions regarding the breach. In response to the breach and OCR's review, the CE took a number of actions to address and mitigate the effects of the breach including: disabling the compromised server and replacing it with a new server; examining all work stations to ensure they were secure; and, establishing user controls and updating its password management procedures. In the course of its review, OCR provided the CE with technical assistance regarding necessary changes to its policies and procedures, and the requirements to conduct periodic thorough enterprise wide risk analyses and to review and update its risk management process.
Section F.5 / Modelled cost
13,000 individuals through IBM's per-record figures
Modelled cost / method shown, not a disclosed cost
ModelledIBM 2025 customer PII, $160 per record
$2.08M
13,000 x $160
IBM 2026 customer PII, $192 per record
$2.50M
13,000 x $192
Method: individuals affected, as reported by Siouxland Anesthesiology, Ltd. 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
South Dakota statute and the HIPAA rule
State notification statute
South Dakota: S.D. Codified Laws 22-40-19 et seq.
- Notice to individuals
- No later than 60 days from discovery or notification of the breach
- Attorney general threshold
- More than 250 South Dakota residents (Within the 60-day window)
- Private right of action
- No: No PROA; only the Attorney General can enforce
- Penalty
- Up to $10,000 per day per violation; may be prosecuted as a deceptive practice
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
South Dakota filings closest in size
Neighbours by size rank among South Dakota filings in 2015, topped up from other years where 2015 has too few. Filings of 10,000 or more link to their own page.
| Covered entity | Type | Individuals | Submitted | Breach type | Location | BA |
|---|---|---|---|---|---|---|
| Black Hills Regional Eye Institute | Healthcare Provider | 106,763 | 31 Mar 2025 | |||
| Huron Regional Medical Center, Inc.Open | Healthcare Provider | 25,398 | 6 Jun 2025 | |||
| Plastic Surgery Associates of South Dakota | Healthcare Provider | 10,229 | 27 Jul 2017 | |||
| VA Black Hills Health Care System | Healthcare Provider | 1,168 | 4 Aug 2015 | |||
| Sioux Falls VA Health Care System | Healthcare Provider | 1,111 | 30 Jul 2015 |
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 5785.
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.