Main Street Research LLC

Q1 2026 13F-HR Holdings

Location
Sausalito, CA
Holdings as of
3/31/2026
Date filed
4/30/2026
Form type
13F-HR
Num holdings
148
Total value ($000)
$1,718,528
Net value change ($000)
-29,648 (-1.7%)
New positions
31
Sold out positions
12
Turnover %
17.3%
Sector allocation + QoQ delta (equities-only)
Prev filing: 2/9/2026 Next filing: — SEC filing

Snapshot: Change Analysis

Compared to Q4 2025
Methodology: sector metrics are equities-only; instrument mix chart is ex-options; options exposure is shown separately. Why this matters.
Top Adds (Value $000, Stocks/ETFs)
GLW 52,718 NEW
BHP 37,767 NEW
AZN 37,599 NEW
RY 36,007 NEW
MU 35,341 2325.1%
KEYS 31,890 NEW
XBI 28,525 64.9%
AAPL 23,330 29.5%
ASML 12,140 28.3%
GEV 12,119 37.7%
Top Reduces (Value $000, Stocks/ETFs)
HOOD -59,986 -99.6%
V -57,958 -94.9%
MSFT -56,346 -69.3%
PLTR -53,731 -68.7%
UBER -35,690 -97.7%
AZN -34,126 -100.0%
IBN -30,460 -100.0%
BCS -24,821 -58.0%
BKNG -20,388 -100.0%
META -16,529 -28.9%
Instrument mix + QoQ Δ (ex-options)
How this table is calculated: SEC VALUE ($000) is used as reported. For derivatives (PUT/CALL/WARRANT/RIGHT), SEC value represents reported underlying exposure, not premium cash paid/received. Column % is bucket-based: non-options share is calculated inside non-option total, options share is calculated inside options total. Details.
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Instrument:
Issuer Name Ticker Sector Industry Class History Value ($000) % Shares Shares Δ Shares Δ% Value Δ ($000) Value Δ% Principal Option Type