ACIU vs IBAC: Correlation
How closely do AC Immune SA (ACIU) and IB Acquisition Corp. (IBAC) trade together? Their weekly returns over three years give a correlation of -0.19, which is negative.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are ACIU and IBAC?
On 3 years of weekly data the ACIU/IBAC correlation comes out at -0.19, negative, meaning they tend to move in opposite directions. The relationship has been stable: the 1-year correlation (-0.15) sits close to the 3-year figure. The 5-year figure is n/a, and annualized covariance runs at -27.1 %².
IBAC is close to the least connected end of ACIU's tracked universe, ranking #9 of 11. Their recent paths diverged sharply: over the last 12 months ACIU outperformed by 27.6 percentage points (+30.9% for ACIU against +3.3% for IBAC). Note the risk asymmetry: ACIU runs 32.9 times the annualized volatility of the other leg, so equal-weighting the two is not an equal-risk position.
How is this computed?
Pearson correlation on weekly returns: ρ(A,B) = cov(rA, rB) / (σA · σB), over windows of 52, 156 and 260 weeks. Covariance is annualized (×52) and expressed in %². Full definitions on the methodology page.
ACIU vs IBAC: side by side
| ACIU (AC Immune SA) | IBAC (IB Acquisition Corp.) | |
|---|---|---|
| 1-year return | +30.9% | +3.3% |
| 5-year return | -61.2% | n/a |
| Volatility (ann.) | 69.0% | 2.1% |
| Beta vs S&P 500 | 1.20 | -0.00 |
| Max drawdown (3Y) | -70.4% | -3.2% |
| Market cap | $0.3B | $0.1B |
| P/E (trailing) | – | – |
| Dividend yield | 0.00% | 0.00% |
| Sector / category | US Listed | US Listed |
Year-by-year returns
| Year | ACIU | IBAC |
|---|---|---|
| 2022 | -58.8% | – |
| 2023 | +145.1% | – |
| 2024 | -46.0% | – |
| 2025 | +16.3% | +3.7% |
| 2026 | -13.7% | +3.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are ACIU and IBAC good diversifiers for each other?
By historical standards, yes. A correlation of -0.19 means the two rarely move for the same reasons.
FAQ
What is the correlation between ACIU and IBAC?
Using weekly returns as of 2026-08-27: -0.19 over 3 years, with -0.15 over the last year and n/a over 5 years.
Is IBAC a good diversifier for ACIU?
By historical standards, yes. A correlation of -0.19 means the two rarely move for the same reasons.
What does a correlation of -0.19 mean?
On the −1 to +1 scale, -0.19 describes how much the two returns move together: +1 is lockstep, 0 is independence, negative values mean opposite directions. It says nothing about which performed better.
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Related comparisons
Hubs: ACIU correlations · IBAC correlations
