Berkshire Hathaway Inc. Class B (BRK-B)
Daily ERM3 factor decomposition: how much of BRK-B's variance is explained by the market, its sector, and its subsector — and the ETF notionals that would neutralize each layer.
- Price
- $541.96
- Market cap
- $1.16T
- 23-day vol
- 11.5%
- Sector proxy
- XLF
- Subsector proxy
- KIE
Risk DNA
24% of BRK-B's variance is systematic (explainable by market, sector, and subsector factors); the rest is stock-specific.
BRK-B carries 72% stock-specific risk against a peer average of 64% — more of what happens here is specific to this name than is typical for its cohort.
Market (-6.2%) covaried negatively with BRK-B over this window, offsetting its variance rather than adding to it. Clamped to 0% for the bar and the remaining layers renormalized, so the percentages above sum to 100.
ETF hedge ratios
Dollars of ETF to short per $1 of BRK-B held — executable hedge weights, not regression betas. L1 hedges market only; L3 adds sector and subsector layers.
| Level | Market (SPY) | Sector (XLF) | Subsector (KIE) | Explained risk |
|---|---|---|---|---|
| L1 | $0.07 | — | — | -6.2% |
| L2 | $0.41 | $-0.58 | — | 17.4% |
| L3 | $0.26 | $-0.30 | $-0.31 | 24.1% |
Data as of October 30, 2026. Updated daily from the ERM3 pipeline.
13F filers holding BRK-B
From the most recent quarterly 13F filings in our tracked filer universe, largest reported position first.
Browse every tracked 13F filer.
Go deeper on BRK-B
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