Q2 2026 13F · SEC CIK 1513211

Main Street Research LLC

Wealth managerFiled 2026-07-29 for Q2 2026. Open the filing ↗ · All SEC filings ↗

Reported 13F value: $2.1B
Reported positions: 140
Top holdings a year, 3 yrs: +17.1%
Assets under management: $2.7B

Main Street Research LLC is a wealth manager that reported 140 positions worth $2.1B in its Q2 2026 13F, filed 2026-07-29. Its largest holdings were Nvidia Corporation Com (NVDA, 6.0%), Micron Technology Inc (MU, 5.9%), Apple Inc (AAPL, 5.5%). A portfolio copying its top holdings returned 17.1% a year over the last 3 years, against 20.4% for the S&P 500.

Main Street Research LLC holdings largest 50 of 140 positions.

Weights are shares of the filer's total reported 13F value, compared with Q1 2026. Share changes may reflect splits; weight changes also reflect price moves. A 13F shows long US-listed positions only, up to 135 days after the fact.

Main Street Research LLC 13F holdings
Stock	% of 13F value	Q1 2026	Shares	Share change	Reported value
NVDANvidia Corporation Com	6.0%	6.3%	630,053	+1.5%	$126.1M
MUMicron Technology Inc	5.9%	2.1%	108,636	-0.4%	$125.4M
AAPLApple Inc	5.5%	6.0%	406,129	+0.6%	$117.5M
GOOGLAlphabet Inc	5.3%	5.2%	316,947	+1.7%	$113.3M
TSMTaiwan Semiconductor Manufac	5.1%	4.4%	228,429	+2.4%	$109.1M
GLWCorning Inc.	4.8%	3.1%	394,058	+1.6%	$100.7M
XBISpdr Series Trust	4.3%	4.2%	576,754	+1.6%	$91.3M
ISCFIshares Tr	4.1%	4.8%	2,027,356	+3.5%	$87.8M
ASMLAsml Hldg NV	4.0%	3.2%	42,396	+1.7%	$84.3M
AVGOBroadcom Inc	3.8%	3.8%	213,841	+0.7%	$80.8M
JPMJpmorgan Chase & Co	3.5%	3.8%	226,299	+1.1%	$74.1M
EWYIshares Inc	3.4%	2.6%	360,865	-0.3%	$72.9M
CATCaterpillar Inc Com	3.1%	2.5%	61,759	+1.1%	$65.8M
AMZNAmazon Com Inc Com	3.1%	3.3%	274,738	+2.1%	$65.5M
GEVGe Vernova Inc	2.8%	2.6%	50,802	+0.2%	$59.7M
APHAmphenol Corp	2.6%	2.2%	308,716	+2.5%	$54.4M
JNJJohnson & Johnson	2.3%	2.7%	188,640	+0.9%	$47.9M
RYRoyal Bank of Canada	2.2%	2.1%	227,136	+2.1%	$47.0M
COSTCostco Whsl Corp New	2.1%	2.7%	47,497	+2.9%	$44.4M
BHPBhp Billiton Limited	2.1%	2.2%	528,051	+1.7%	$44.0M
BCSBarclays PLC	2.1%	1.0%	1,621,490	+90.5%	$43.6M
METAMeta Platforms Inc Class A	1.9%	2.4%	72,187	+1.7%	$40.7M
KEYSKeysight Technologies Inc Com	1.9%	1.9%	115,108	+1.9%	$40.3M
CCJCameco Corp Com	1.9%	2.5%	391,529	+0.6%	$39.9M
WMTWalmart Inc	1.9%	2.5%	348,650	+1.1%	$39.5M
AZNAstrazeneca PLC Ord	1.8%	2.2%	197,417	+3.6%	$37.4M
ROSTRoss Stores Inc.	1.5%	—	150,755	—	$32.1M
FTITechnipfmc PLC	1.3%	—	413,657	—	$27.4M
MSFTMicrosoft Corp	1.2%	1.5%	69,182	+2.4%	$25.8M
PGProcter & Gamble Co Com	1.0%	1.3%	151,073	-0.4%	$22.2M
MCKMckesson Corp Com	1.0%	3.4%	28,475	-58.0%	$21.5M
FICOFair Isaac Corp	0.5%	0.5%	9,580	+13.2%	$11.4M
GOOGAlphabet Inc	0.4%	0.4%	22,707	-3.1%	$8.0M
PANWPalo Alto Networks Inc	0.4%	0.3%	23,343	-31.4%	$8.0M
BRK-BBerkshire Hathaway Inc Del	0.3%	0.3%	11,980	+0.0%	$6.0M
ANETArista Networks Inc	0.3%	0.3%	34,937	-0.1%	$5.9M
TSLATesla Inc Com	0.3%	0.3%	12,943	+4.9%	$5.4M
SCHWSchwab Charles Corp	0.2%	0.3%	45,887	-1.0%	$4.2M
WFCWells Fargo Co New	0.2%	0.2%	48,542	+3.5%	$4.0M
BRK-ABerkshire Hathaway Inc Del	0.2%	0.2%	5	+0.0%	$3.7M
IXUSIshares Core Msci Total International St	0.2%	0.2%	39,073	+1.3%	$3.7M
LLYLilly Eli & Co	0.2%	0.2%	2,746	-5.6%	$3.3M
VVisa Inc Com Cl A	0.2%	0.2%	9,369	-8.6%	$3.2M
XOMExxon Mobil Corp	0.1%	0.2%	22,437	-6.2%	$3.1M
ADSKAutodesk Inc	0.1%	0.2%	14,240	-1.1%	$2.8M
URTHIshares Inc	0.1%	0.2%	13,511	-8.4%	$2.7M
CVXChevron Corp New	0.1%	0.2%	16,080	-4.6%	$2.7M
SPYSpdr S&p 500 ETF Tr	0.1%	—	3,485	—	$2.6M
ABBVAbbvie Inc	0.1%	0.1%	9,721	-5.2%	$2.4M
MCDMcdonalds Corp Com	0.1%	0.3%	8,913	-42.4%	$2.4M

What Main Street Research LLC bought and sold in Q2 2026, against Q1 2026.

New positions

Q1 2026's filing was too long to tell new positions apart.

Share counts compared with the Q1 2026 13F; a split also changes share counts. The latest filing lists more than 50 positions, so a position that left the top 50 may still be held.

How the holdings did against the S&P 500.

1 year: +9.1% /yr; S&P 500 +20.1%
3 years: +17.1% /yr; S&P 500 +20.4%
5 years: +9.7% /yr; S&P 500 +11.6%

A portfolio of the filer's 20 largest 13F positions, weighted by value and rebuilt each quarter on the day the filing became public. 13Fs show long US-listed positions only, so this is an estimate of the stock picks, not the fund's reported returns.

Reported 13F value by quarter.

13F value by quarter
Quarter	13F value	Positions
Q2 2026	$2.1B	140
Q1 2026	$1.7B	148
Q4 2025	$1.7B	129
Q3 2025	$1.9B	129
Q2 2025	$1.6B	115
Q1 2025	$1.5B	101
Q4 2024	$1.6B	110
Q3 2024	$1.6B	109
Q2 2024	$1.5B	103
Q1 2024	$1.5B	107
Q4 2023	$1.2B	106
Q3 2023	$970.6M	91

Questions about Main Street Research LLC's portfolio

What stocks does Main Street Research LLC own?

Main Street Research LLC's latest 13F, for Q2 2026 and filed Jul 29, 2026, lists 140 positions worth $2.1B. The largest are Nvidia Corporation Com (NVDA) at 6.0%, Micron Technology Inc (MU) at 5.9%, Apple Inc (AAPL) at 5.5%, Alphabet Inc (GOOGL) at 5.3% and Taiwan Semiconductor Manufac (TSM) at 5.1%.

What did Main Street Research LLC buy last quarter?

In Q2 2026, Main Street Research LLC added Barclays PLC (BCS) (+90.5% shares) and Fair Isaac Corp (FICO) (+13.2% shares), compared with its Q1 2026 filing.

What did Main Street Research LLC sell last quarter?

In Q2 2026, Main Street Research LLC cut from its top 50 World Gold Tr (GLDM), cut from its top 50 Palantir Technologies Inclass Class A (PLTR), cut from its top 50 Ishares Bitcoin Trust ETF (IBIT), Mckesson Corp Com (MCK) (-58.0% shares), Mcdonalds Corp Com (MCD) (-42.4% shares) and Palo Alto Networks Inc (PANW) (-31.4% shares), compared with its Q1 2026 filing.

How has Main Street Research LLC's portfolio performed?

A portfolio copying Main Street Research LLC's 20 largest 13F holdings each quarter, from the day each filing was public, returned +17.1% a year over the last 3 years, against +20.4% for the S&P 500. Over 1 year: +9.1% against +20.1%. Over 5 years: +9.7% a year against +11.6%.

When is Main Street Research LLC's next 13F filing due?

13F filings are due 45 days after each quarter ends. Main Street Research LLC's filing for the quarter ending Sep 30, 2026 is due by Nov 14, 2026; this page updates the day after it is published.

How much money does Main Street Research LLC manage?

Main Street Research LLC reported $2.7B of regulatory assets under management on its latest SEC Form ADV. Its 13F, which covers only US-listed stocks and options, totals $2.1B.