Main Street Research LLC

CIK

1513211

Location

SAUSALITO, CA

Portfolio Value

Mid $1,838,817,617

Diversification

Diversified

Filing Date

Global Rank

#1,385 / 8,650 ▲ 39

Top Industry

Semiconductors 24.4%

3Y Alpha vs SPY

+52.3%

Period ended 56 days ago

Filed Jul 29, 2026 · 27d

26 quarters · since Mar 2020

Clone Performance

Aug 2023–Aug 2026 · vs SPY

Hypothetical growth of buying every stock this filer reported holding, rebalancing on each filing and indexed to the same start. Option positions cannot be bought this way and are left out.

Cloned portfolio

+406.5%

SPY

+73.5%

Annualised alpha

+51.6%

Max drawdown

−19.9%

Estimate. 13F holdings are quarter-lagged, so the clone rebalances about 45 days after each period end — when the filing becomes public — and it excludes option and short positions. Returns use comparable raw closes and exclude dividends; a captured split can shorten the simulated window. It tracks 100% of reported value on average across 13 quarters. Past performance does not predict future results.

Portfolio Concentration

116 tracked positions · as of Jun 30, 2026 · Δ vs Mar 31, 2026

Top Position

6.9%

−0.5 pts

Top 5

32.2%

+1.6 pts

Top 10

54.2%

+4.0 pts

HHI

404

Diversified+21

Portfolio Trend

26 quarters · across all stocks

Sector Breakdown

As of Jun 30, 2026

Sector	% Portfolio	Value	Positions
Technology	49.4%	$908,666,644	37
Financial Services	10.2%	$187,311,028	16
Communication Services	8.4%	$155,348,027	6
Industrials	7.1%	$131,425,073	12
Healthcare	6.3%	$116,445,008	16
Consumer Defensive	5.9%	$109,019,425	9
Consumer Cyclical	5.9%	$108,750,253	10
Energy	4.0%	$73,281,008	5
Basic Materials	2.4%	$44,036,228	2
Unclassified	0.2%	$4,534,923	3

Last Quarter's Activity

Export CSV

Jun 30, 2026 vs Mar 31, 2026

Added To

Positions the filer increased

25 positions

Ticker	Company	Δ Shares	Shares	Value
BCS	Barclays PLC	+770,519	1,621,490	$43,553,221
NVDA	Nvidia Corp	+9,277	630,053	$126,067,304
BHP	BHP Group Ltd	+8,839	528,051	$43,991,928
APH	Amphenol Corp /De/	+7,673	308,716	$54,432,805
AZN	Astrazeneca PLC	+6,773	197,417	$37,434,211
GLW	Corning Inc /Ny	+6,340	394,058	$100,654,234
AMZN	Amazon Com Inc	+5,545	274,738	$65,481,054
TSM	Taiwan Semiconductor Manufacturing Co Ltd	+5,270	228,429	$109,090,837
RY	Royal Bank Of Canada	+4,568	227,136	$47,010,337
WMT	Walmart Inc.	+3,781	348,650	$39,488,099
AAPL	Apple Inc.	+2,551	406,129	$117,517,487
JPM	Jpmorgan Chase & Co	+2,537	226,299	$74,074,451
CCJ	Cameco Corp	+2,452	391,529	$39,881,143
MUFG	Mitsubishi Ufj Financial Group Inc	+2,273	32,721	$650,820
KEYS	Keysight Technologies, Inc.	+2,171	115,108	$40,295,857
JNJ	Johnson & Johnson	+1,758	188,640	$47,908,900
MTCH	Match Group, Inc.	+1,735	8,746	$332,785
WFC	Wells Fargo & Company/Mn	+1,660	48,542	$4,011,510
MSFT	Microsoft Corp	+1,640	69,182	$25,806,269
AVGO	Broadcom Inc.	+1,439	213,841	$80,778,437
INTC	Intel Corp	+1,431	7,350	$1,026,280
KLAC	Kla Corp	+1,427	1,604	$483,942
COST	Costco Wholesale Corp /New	+1,358	47,497	$44,432,018
META	Meta Platforms, Inc.	+1,225	72,187	$40,662,215
DAL	Delta Air Lines, Inc.	+1,172	6,263	$586,592
No positions match the current search.

Trimmed

Positions the filer reduced

25 positions

Ticker	Company	Δ Shares	Shares	Value
PLTR	Palantir Technologies Inc.	−156,203	11,444	$1,335,171
MCK	Mckesson Corp	−39,299	28,475	$21,515,710
GOOGL	Alphabet Inc.	−18,276	316,947	$113,267,349
PANW	Palo Alto Networks Inc	−10,681	23,343	$7,960,429
MCD	Mcdonalds Corp	−6,570	8,913	$2,409,273
T	At&T Inc.	−6,122	14,071	$291,269
CMCSA	Comcast Corp	−2,483	11,037	$270,958
UNP	Union Pacific Corp	−1,716	2,413	$656,336
BMY	Bristol Myers Squibb Co	−1,690	5,252	$302,620
XOM	ExxonMobil Holdings Corp	−1,487	22,437	$3,067,586
ABT	Abbott Laboratories	−1,366	2,493	$226,214
MRK	Merck & Co., Inc.	−1,223	8,298	$1,066,293
CRM	Salesforce, Inc.	−1,122	5,802	$908,941
V	Visa Inc.	−877	9,369	$3,214,410
CVX	Chevron Corp	−771	16,080	$2,665,420
HOOD	Robinhood Markets, Inc.	−709	2,581	$258,822
UBER	Uber Technologies, Inc	−685	10,806	$779,760
CLX	Clorox Co /De/	−603	8,934	$852,660
XYL	Xylem Inc.	−590	2,729	$322,595
PG	PROCTER & GAMBLE Co	−554	151,073	$22,153,344
SYK	Stryker Corp	−542	1,221	$384,419
ABBV	AbbVie Inc.	−537	9,721	$2,446,192
MU	Micron Technology Inc	−473	108,636	$125,397,448
SCHW	Schwab Charles Corp	−473	45,887	$4,233,993
CSCO	Cisco Systems, Inc.	−375	9,682	$1,137,247
No positions match the current search.

New Positions

Positions the filer opened this quarter

10 positions

Ticker	Company	Shares	Value
ROST	Ross Stores, Inc.	150,755	$32,088,201
FTI	TechnipFMC plc	413,657	$27,425,459
HUT	Hut 8 Corp.	3,986	$460,163
UAL	United Airlines Holdings, Inc.	2,344	$318,760
MNST	Monster Beverage Corp	2,967	$285,188
QCOM	Qualcomm Inc/De	1,375	$254,086
ABEO	Abeona Therapeutics Inc.	38,514	$238,016
HIMS	Hims & Hers Health, Inc.	6,200	$214,954
KO	Coca Cola Co	2,558	$207,888
DDOG	Datadog, Inc.	791	$205,944
No positions match the current search.

Sold Out

Positions the filer fully exited

21 positions

Ticker	Company	Shares	Value
GLDM	World Gold Trust	469,451	$43,513,413
IBIT	iShares Bitcoin Trust ETF	196,085	$7,533,585
DIS	Walt Disney Co	10,730	$1,034,157
GLD	Spdr Gold Trust	1,806	$777,103
ISRG	Intuitive Surgical Inc	839	$386,770
BSX	Boston Scientific Corp	5,993	$376,060
ACN	Accenture plc	1,683	$333,722
INTU	Intuit Inc.	712	$307,854
COIN	Coinbase Global, Inc.	1,550	$270,645
COP	Conocophillips	1,950	$257,400
NFLX	Netflix Inc	2,673	$257,008
MA	Mastercard Inc	493	$246,332
ADBE	Adobe Inc.	1,005	$244,295
AXP	American Express Co	773	$233,817
HD	Home Depot, Inc.	686	$225,618
TMUS	T-Mobile US, Inc.	1,070	$224,732
COF	Capital One Financial Corp	1,180	$215,267
NEE	Nextera Energy Inc	2,266	$210,466
TDY	Teledyne Technologies Inc	338	$204,493
VRT	Vertiv Holdings Co	810	$202,969
OMDA	Omada Health, Inc.	15,909	$199,976
No positions match the current search.

Portfolio Positions

Compact Export CSV View 13F filing

116 tracked positions · $1,838,817,617 total · filing declares 140 positions · $2,118,491,302 · as of Jun 30, 2026

All sectors Basic Materials Communication Services Consumer Cyclical Consumer Defensive Energy Financial Services Healthcare Industrials Technology

Showing 1–50 of 116 positions by value · page 1 of 3

Ticker	Company	Type	Shares	Δ Shares	Value (USD)	% Δ Value	% of Portfolio
NVDA	Nvidia Corp Technology	Added	630,053	+9,277	$126,067,304	+16.4%	6.86%
MU	Micron Technology Inc Technology	Reduced	108,636	-473	$125,397,448	+240.2%	6.82%
AAPL	Apple Inc. Technology	Added	406,129	+2,551	$117,517,487	+14.7%	6.39%
GOOGL	Alphabet Inc. Communication Services	Reduced	316,947	-18,276	$113,267,349	+17.5%	6.16%
TSM	Taiwan Semiconductor Manufacturing Co Ltd Technology	Added	228,429	+5,270	$109,090,837	+44.7%	5.93%
GLW	Corning Inc /Ny Technology	Added	394,058	+6,340	$100,654,234	+90.9%	5.47%
ASML	Asml Holding NV Technology	Added	42,396	+709	$84,344,294	+53.2%	4.59%
AVGO	Broadcom Inc. Technology	Added	213,841	+1,439	$80,778,437	+22.9%	4.39%
JPM	Jpmorgan Chase & Co Financial Services	Added	226,299	+2,537	$74,074,451	+12.5%	4.03%
CAT	Caterpillar Inc Industrials	Added	61,759	+649	$65,767,159	+51.9%	3.58%
AMZN	Amazon Com Inc Consumer Cyclical	Added	274,738	+5,545	$65,481,054	+16.8%	3.56%
GEV	GE Vernova Inc. Industrials	Added	50,802	+110	$59,685,237	+34.9%	3.25%
APH	Amphenol Corp /De/ Technology	Added	308,716	+7,673	$54,432,805	—	2.96%
JNJ	Johnson & Johnson Healthcare	Added	188,640	+1,758	$47,908,900	+4.9%	2.61%
RY	Royal Bank Of Canada Financial Services	Added	227,136	+4,568	$47,010,337	+30.6%	2.56%
COST	Costco Wholesale Corp /New Consumer Defensive	Added	47,497	+1,358	$44,432,018	−3.4%	2.42%
BHP	BHP Group Ltd Basic Materials	Added	528,051	+8,839	$43,991,928	+16.5%	2.39%
BCS	Barclays PLC Financial Services	Added	1,621,490	+770,519	$43,553,221	+141.9%	2.37%
META	Meta Platforms, Inc. Communication Services	Added	72,187	+1,225	$40,662,215	+0.2%	2.21%
KEYS	Keysight Technologies, Inc. Technology	Added	115,108	+2,171	$40,295,857	+26.4%	2.19%
CCJ	Cameco Corp Energy	Added	391,529	+2,452	$39,881,143	−5.6%	2.17%
WMT	Walmart Inc. Consumer Defensive	Added	348,650	+3,781	$39,488,099	−7.9%	2.15%
AZN	Astrazeneca PLC Healthcare	Added	197,417	+6,773	$37,434,211	−0.4%	2.04%
ROST	Ross Stores, Inc. Consumer Cyclical	NEW	150,755	NEW	$32,088,201	NEW	1.75%
FTI	TechnipFMC plc Energy	NEW	413,657	NEW	$27,425,459	NEW	1.49%
MSFT	Microsoft Corp Technology	Added	69,182	+1,640	$25,806,269	+3.2%	1.40%
PG	PROCTER & GAMBLE Co Consumer Defensive	Reduced	151,073	-554	$22,153,344	+1.2%	1.20%
MCK	Mckesson Corp Healthcare	Reduced	28,475	-39,299	$21,515,710	−63.3%	1.17%
FICO	Fair Isaac Corp Technology	Added	9,580	+1,116	$11,445,992	+26.7%	0.62%
PANW	Palo Alto Networks Inc Technology	Reduced	23,343	-10,681	$7,960,429	+45.9%	0.43%
BRK-B	Berkshire Hathaway Inc Financial Services	Reduced	11,980	-3	$5,994,672	−35.8%	0.33%
ANET	Arista Networks, Inc. Technology	Reduced	34,937	-44	$5,935,097	+38.2%	0.32%
TSLA	Tesla, Inc. Consumer Cyclical	Added	12,943	+606	$5,443,825	+18.7%	0.30%
SCHW	Schwab Charles Corp Financial Services	Reduced	45,887	-473	$4,233,993	−2.8%	0.23%
WFC	Wells Fargo & Company/Mn Financial Services	Added	48,542	+1,660	$4,011,510	+7.5%	0.22%
LLY	ELI LILLY & Co Healthcare	Reduced	2,746	-162	$3,293,635	+23.1%	0.18%
V	Visa Inc. Financial Services	Reduced	9,369	-877	$3,214,410	+3.8%	0.17%
XOM	ExxonMobil Holdings Corp Energy	Reduced	22,437	-1,487	$3,067,586	−24.4%	0.17%
ADSK	Autodesk, Inc. Technology	Reduced	14,240	-163	$2,768,540	−19.7%	0.15%
CVX	Chevron Corp Energy	Reduced	16,080	-771	$2,665,420	−23.5%	0.14%
SPY	Spdr S&P 500 ETF Trust	Added	3,485	+222	$2,602,493	+22.6%	0.14%
ABBV	AbbVie Inc. Healthcare	Reduced	9,721	-537	$2,446,192	+9.6%	0.13%
MCD	Mcdonalds Corp Consumer Cyclical	Reduced	8,913	-6,570	$2,409,273	−49.9%	0.13%
AMD	Advanced Micro Devices Inc Technology	Added	3,308	+163	$1,921,650	+200.4%	0.10%
PLTR	Palantir Technologies Inc. Technology	Reduced	11,444	-156,203	$1,335,171	−94.6%	0.07%
MMM	3M Co Industrials	Reduced	7,610	-260	$1,232,135	+7.8%	0.07%
CSCO	Cisco Systems, Inc. Technology	Reduced	9,682	-375	$1,137,247	+45.7%	0.06%
QQQ	Invesco Qqq Trust, Series 1	Reduced	1,531	-238	$1,127,428	+10.4%	0.06%
RTX	RTX Corp Industrials	Reduced	5,752	-314	$1,091,326	−6.7%	0.06%
MRK	Merck & Co., Inc. Healthcare	Reduced	8,298	-1,223	$1,066,293	−6.9%	0.06%

Covers the securities this platform tracks: U.S.-listed common stock and the put/call positions reported on it. A 13F can also report security types outside that coverage — preferred shares, bonds, warrants, untracked share classes — so the filing's own declared total can exceed the figures above. The source filing is linked at the top of this table.