Berkshire Hathaway Inc.
AUM
+$289B
Turnover
+2.8%
Large CapGrowthLong-term Holder
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Bundled catalog snapshot 2026-08-23T15:10:38.640854+00:00135 public workspaces
Daily public research
Selected for Oct 17, 2026 · refreshes daily
Berkshire entity research
Berkshire Hathaway 13F holdings and portfolio
Explore the latest disclosed holdings, concentration, sector exposure and a curated public research conversation.
13F holdingsCurated Q&A
View researchAI strategy optimization
What the Agent changed, and what it proved
Each default workspace ran the staged optimization: baseline, factor evidence, challenger plan, out-of-sample evaluation, then a deterministic verdict. Only accepted candidates changed the live strategy.
Accepted and live: 5/7Challengers tested: 55Rejected by policy: 49
Dodge & Cox Funds - Dodge & Cox Stock Fund
Single-13F workspace
Sharpe (out-of-sample)
0.69
baseline 0.65
Return
270.34%
baseline 218.49%
ΔSharpe +0.044ΔReturn +51.9pp
Change: tilt weights toward high beta252d (strength 0.55)
Acceptance evidence
Rejected: 6/8 · t=2.15 / bar 1.99
r01-c03-set_rule rejected — better return but turnover +40pp, beyond tolerance
The Warren Buffett Lineage Pack
Multi-13F workspace
Sharpe (out-of-sample)
0.60
baseline 0.56
Return
226.50%
baseline 186.82%
ΔSharpe +0.043ΔReturn +39.7pp
Change: tilt weights toward high beta252d (strength 0.4)
Acceptance evidence
Rejected: 7/8 · t=1.70 / bar 1.42
r00-c05-factor_tilt rejected — positive (ΔSharpe +0.010) but below the bar (t=1.70)
Berkshire Hathaway Inc.
Single-13F workspace
Sharpe (out-of-sample)
0.55
baseline 0.51
Return
143.28%
baseline 127.48%
ΔSharpe +0.038ΔReturn +15.8pp
Change: drop holdings whose qualityCompositeScore is below 40
Acceptance evidence
Rejected: 7/8 · t=2.20 / bar 2.12
r01-c07-set_parameter rejected — improved, below the bar (t=1.50 vs bar 2.14)
Harris Associates Investment Trust - Oakmark Fund
Single-13F workspace
Sharpe (out-of-sample)
0.68
baseline 0.66
Return
273.23%
baseline 234.04%
ΔSharpe +0.029ΔReturn +39.2pp
Change: tilt weights toward high beta252d (strength 0.35)
Acceptance evidence
Rejected: 7/8 · t=1.50 / bar 1.42
r00-c02-turnover_guard rejected — positive (ΔSharpe +0.038) but below the bar (t=1.51)
Out-of-sample figures come from each workspace's own backtest; they move as the data is refreshed.See all optimization results
13F universe
13F Discovery Radar
Track the latest 13F rotation signals across managers, industries, and high-conviction stock moves. 2026-03-31 -> 2026-06-30.
Managers
132
Industries
25
Stocks
500
Latest active flow
+$16B
2026-06-30
Equity withdrawal proxy
+$451B
2026-03-31 -> 2026-06-30
SPY indexed
+174.8%
2026-06-30
Capital Rotation Timeline
Stacked sectors show share-count-implied active capital; the amber line tracks SPY.
Latest flow
+$16B
SPY
+174.8%
FinancialsHealth CareIndustrialsInformation TechnologyConsumer DiscretionaryCommunication ServicesWithdrawal proxySPY
Macro Rotation Heatmap
Area ranks current 13F exposure. Color shows active flow momentum from the latest filings.
All industriesNet inflowNet outflow
Active flow momentumTrimmedFlatAdded
Largest industry rotations
Semiconductors and Semiconductor Equipment
Information Technology
-$15B
-12.6%50 Buyers / 60 Sellers
Capital Goods
Industrials
+$7.8B
+5.5%64 Buyers / 75 Sellers
Media and Entertainment
Communication Services
+$7.2B
+5.5%68 Buyers / 76 Sellers
Transportation
Industrials
+$6.3B
+16.1%47 Buyers / 55 Sellers
Software and Services
Information Technology
+$4.2B
+3.7%70 Buyers / 67 Sellers
Financial Services
Financials
+$3.3B
+1.6%77 Buyers / 80 Sellers
Highest conviction stock moves
| Ticker | Industry | Active flow | Conviction |
|---|---|---|---|
MELI MercadoLibre, Inc. | Consumer Discretionary Distribution and Retail | -$5.8B | +0.2% |
JPM JPMorgan Chase & Co. | Banks | +$5.5B | +0.6% |
GOOGL Alphabet Inc. | Media and Entertainment | +$4.4B | +1.9% |
GEV GE Vernova Inc. | Capital Goods | +$4.2B | +1.1% |
V Visa Inc. | Financial Services | +$3.8B | +0.8% |
GE General Electric Company | Capital Goods | +$3.7B | +0.9% |
AMZN Amazon.com, Inc. | Consumer Discretionary Distribution and Retail | +$3.6B | +2.6% |
NVDA NVIDIA Corporation | Semiconductors and Semiconductor Equipment | -$3.1B | +1.0% |
Largest manager books
Fisher Asset Management, LLC
AUM
+$239B
Turnover
+10.6%
Large CapGrowthLong-term Holder
PRIMECAP Management Company
AUM
+$158B
Turnover
+5.1%
Large CapGrowthLong-term Holder
Dodge & Cox Funds - Dodge & Cox Stock Fund
AUM
+$103B
Turnover
+7.0%
Large CapGarpLong-term Holder