UnitedHealth Group (Change Healthcare)
The Change Healthcare ransomware attack disrupted US claims, pharmacy and payment infrastructure on a national scale.
-5.3% UNH vs +5.4% SPY
This site shows how share prices moved after an incident became public. It does not prove that the incident caused the move. Company news, sector moves and the wider market can affect every result. Educational only — not investment advice.
Disclosure timing
When could the market react?
The baseline is the last adjusted close before the news was public. The reaction session is the first close afterward.
- 01Baseline sessionFeb 20, 2024
Normalized to 100 for both UNH and SPY.
- 02Public disclosureFeb 21, 2024 · time unknown
Publication time is not documented; lower timing precision.
- 03First reaction closeFeb 21, 2024
+0.2% company total return versus +0.1% for SPY; +0.1 pp market-relative return.
Disclosure time is unknown; the previous session close is used as baseline.
Time windows
Company vs SPY
Each row uses the last trading session on or before its target date. “Market-relative” is the company return minus the SPY return, in percentage points.
| Window | Endpoint | UNH | SPY | Market-relative | Signal |
|---|---|---|---|---|---|
| First reaction | Feb 21, 2024 | +0.2% | +0.1% | +0.1 pp | Above SPY |
| +7 days | Feb 28, 2024 | -4.4% | +1.9% | -6.3 pp | Below SPY |
| +1 month | Mar 21, 2024 | -5.3% | +5.4% | -10.7 pp | Below SPY |
| +3 months | May 21, 2024 | +0.9% | +7.3% | -6.4 pp | Below SPY |
| +6 months | Aug 21, 2024 | +11.9% | +13.6% | -1.7 pp | Below SPY |
| +12 months | Feb 21, 2025 | -9.1% | +22.3% | -31.4 pp | Below SPY |
Compare with current catalog aggregates
| Window | This case | Catalog median | Catalog mean | n |
|---|---|---|---|---|
| First reaction | +0.1 pp | -0.8 pp | -1.5 pp | 30 |
| +7 days | -6.3 pp | -2.0 pp | -4.0 pp | 30 |
| +1 month | -10.7 pp | -6.6 pp | -6.8 pp | 30 |
| +3 months | -6.4 pp | -5.1 pp | -6.6 pp | 30 |
| +6 months | -1.7 pp | -5.6 pp | -7.5 pp | 30 |
| +12 months | -31.4 pp | -3.7 pp | -10.1 pp | 30 |
Normalized total return
UNH compared with SPY
Baseline session = 100. Adjusted close reflects splits and reinvested distributions.
UnitedHealth Group (Change Healthcare) had -9.1% company total return versus +22.3% for SPY; -31.4 pp market-relative return. The chart shows normalized adjusted-close performance for up to 24 months.
View tabular chart fallback
| Date | UNH | SPY |
|---|---|---|
| Feb 20, 2024 | 100.0 | 100.0 |
| Mar 20, 2024 | 95.2 | 105.1 |
| Apr 19, 2024 | 96.6 | 100.0 |
| May 20, 2024 | 99.7 | 107.0 |
| Jun 20, 2024 | 93.8 | 110.5 |
| Jul 22, 2024 | 108.1 | 112.4 |
| Aug 20, 2024 | 112.3 | 113.2 |
| Sep 19, 2024 | 112.1 | 115.7 |
| Oct 18, 2024 | 110.6 | 118.8 |
| Nov 18, 2024 | 114.5 | 119.5 |
| Dec 18, 2024 | 97.4 | 119.1 |
| Jan 22, 2025 | 101.3 | 123.6 |
| Feb 21, 2025 | 90.9 | 122.3 |
| Mar 24, 2025 | 101.1 | 117.4 |
| Apr 23, 2025 | 83.8 | 109.5 |
| May 22, 2025 | 58.1 | 119.2 |
| Jun 24, 2025 | 60.3 | 124.5 |
| Jul 24, 2025 | 54.9 | 130.1 |
| Aug 22, 2025 | 60.6 | 132.4 |
| Sep 23, 2025 | 69.0 | 136.4 |
| Oct 22, 2025 | 71.7 | 137.3 |
| Nov 20, 2025 | 61.8 | 134.2 |
| Dec 22, 2025 | 64.9 | 141.3 |
| Jan 23, 2026 | 71.2 | 142.2 |
| Feb 20, 2026 | 57.9 | 142.2 |
Price recovery
Recovered
Here, recovery only means that adjusted close reached the baseline again. It does not mean every effect of the incident ended.
- State
- Recovered
- Initial trough
- -4.4% on Feb 28, 2024
- Recovery close
- May 16, 2024
- Calendar days
- 85
- Observation cap
- 24 months after disclosure
Hypothetical $1,000
What would $1,000 have looked like?
Compare $1,000 in UNH with $1,000 in SPY, bought and measured on the same dates.
Entry Feb 26, 2024 Exit Aug 26, 2024
Uses fractional shares and adjusted close. Leaves out taxes, fees and slippage. The holding period starts on the purchase date. This is a historical illustration, not an investment strategy.
Case note
Change Healthcare disconnected systems after identifying an outside threat, interrupting claims, eligibility, pharmacy and payment services relied on across US health care. UnitedHealth later classified and quantified substantial effects.
The first public status acknowledgement occurred February 21, before the parent company’s later SEC filing. The retained evidence establishes the date but not a reliable time, so February 20 is the baseline under the conservative date-only rule.
Evidence
Sources and case review
We qualify each case before checking its price results. These links support the disclosure date, listing, incident and business impact.
- primary Feb 22, 2024UnitedHealth February 2024 Form 8-K UnitedHealth Group / U.S. SEC Supports: Listing, Impact, Description
- secondary Feb 21, 2024US health tech giant Change Healthcare hit by cyberattack TechCrunch Supports: Disclosure, Timing, Impact
- secondary Feb 29, 2024A large US health care tech company was hacked Associated Press Supports: Disclosure, Impact, Description
- Listing evidenceChecked Jul 20, 2026UnitedHealth February 2024 Form 8-K U.S. Securities and Exchange Commission The filing identifies UnitedHealth as the NYSE-listed parent of the affected Change Healthcare business.
Why it is included. UnitedHealth controlled Change Healthcare, whose shutdown disrupted nationally important health-payment infrastructure and later generated material operating and financial effects. Reviewed Jul 20, 2026.