Main Street Research LLC holds a diversified book of 148 stocks worth $1.7B as of Q1 2026 (disclosed Apr 30, 2026, a ~45-day 13F lag). This quarter they opened Corning Inc and trimmed Costco Wholesale Corp. Their largest long position is Nvidia Corp at 6% of the equity book.
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curl -H "Authorization: Bearer YOUR_API_KEY" \ "https://arkolith.com/api/v1/funds/1513211/holdings"
Use Arkolith to show Main Street Research LLC's latest holdings, largest changes, and filing provenance.
Top-heavy: diversified book
Share of the disclosed book in its largest positions. A higher top-5 share means a more concentrated, higher-conviction portfolio.
87% mapped to company sectors
Direct operating-company sectors from our SIC-based security master. ETF/fund and unclassified holdings stay visible separately; this is not ETF look-through exposure.
Estimated $ traded · quarter-end prices, no cost basis
Bars show each stock's share of the portfolio. Click a row for its position history.
| # | Security | Value | Shares | % Port | Last move | History |
|---|---|---|---|---|---|---|
| 1 | Nvidia Corporation COM | $108.3M | 620.8K | 6.3% | ▲+4.2% Added · +25K sh | |
| 2 | Apple Inc COM | $102.4M | 403.6K | 6.0% | ▲+39% Added · +113K sh | |
| 3 | Alphabet Inc CAP STK CL A | $89.7M | 311.8K | 5.2% | ▲+4.8% Added · +14K sh | |
| 4 | Ishares TR INTERNATIONAL SL | $81.9M | 1.96M | 4.8% | ▲+2.7% Added · +51K sh | |
| 5 | Taiwan Semiconductor Manufac SPONSORED ADS | $75.4M | 223.2K | 4.4% | ▲+2.3% Added · +5K sh | |
| 6 | SPDR Series Trust STATE STREET SPD | $72.5M | 567.5K | 4.2% | ▲+57% Added · +207K sh | |
| 7 | JPMorgan Chase & Co COM | $65.8M | 223.8K | 3.8% | ▲+0.8% Added · +2K sh | |
| 8 | Broadcom Inc COM | $65.7M | 212.4K | 3.8% | ▲+3.4% Added · +7K sh | |
| 9 | McKesson Corp COM | $58.6M | 67.8K | 3.4% | ▲+0.6% Added · +413 sh | |
| 10 | Amazon Com Inc COM | $56.1M | 269.2K | 3.3% | ▲+3.6% Added · +9K sh | |
| 11 | ASML Hldg NV N Y REGISTRY SHS | $55.1M | 41.7K | 3.2% | ▲+3.9% Added · +2K sh | |
| 12 | Corning Inc COM | $52.7M | 387.7K | 3.1% | ▲New New position | |
| 13 | Costco Wholesale Corporation COM | $46.0M | 46.1K | 2.7% | ▼−26% Reduced · −16K sh | |
| 14 | Johnson & Johnson COM | $45.7M | 186.9K | 2.7% | ▲+4.2% Added · +8K sh | |
| 15 | Ishares Inc MSCI STH KOR ETF | $44.5M | 361.9K | 2.6% | ▲+1.8% Added · +6K sh | |
| 16 | Ge Vernova Inc COM | $44.2M | 50.7K | 2.6% | ▲+3.1% Added · +2K sh | |
| 17 | World Gold TR SPDR GLD MINIS | $43.5M | 469.5K | 2.5% | ▲+1.5% Added · +7K sh | |
| 18 | Caterpillar Inc COM | $43.3M | 61.1K | 2.5% | ▲+2.6% Added · +2K sh | |
| 19 | Walmart Inc COM | $42.9M | 344.9K | 2.5% | ▲+1.9% Added · +6K sh | |
| 20 | Cameco Corp COM | $42.3M | 389.1K | 2.5% | ▲+1.9% Added · +7K sh | |
| 21 | Meta Platforms Inc CL A | $40.6M | 71.0K | 2.4% | ▼−18% Reduced · −16K sh | |
| 22 | Amphenol Corp CL A | $38.0M | 301.0K | 2.2% | ▲+1.9% Added · +6K sh | |
| 23 | BHP Billiton Limited SPONSORED ADS | $37.8M | 519.2K | 2.2% | ▲New New position | |
| 24 | AstraZeneca PLC ORD | $37.6M | 190.6K | 2.2% | ▲New New position | |
| 25 | Micron Technology Inc COM | $36.9M | 109.1K | 2.1% | ▲20× Added · +104K sh | |
| 26 | Royal BK Cda COM | $36.0M | 222.6K | 2.1% | ▲New New position | |
| 27 | Keysight Technologies Inc COM | $31.9M | 112.9K | 1.9% | ▲New New position | |
| 28 | Microsoft Corp COM | $25.0M | 67.5K | 1.5% | ▼−60% Reduced · −101K sh | |
| 29 | Palantir Technologies Inc CL A | $24.5M | 167.6K | 1.4% | ▼−62% Reduced · −273K sh | |
| 30 | Procter & Gamble Co COM | $21.9M | 151.6K | 1.3% | ▲+0.3% Added · +543 sh | |
| 31 | Barclays PLC ADR | $18.0M | 851.0K | 1.0% | ▼−49% Reduced · −832K sh | |
| 32 | Fair Isaac Corp COM | $9.0M | 8.5K | 0.5% | ▲+240% Added · +6K sh | |
| 33 | Ishares Bitcoin Trust ETF SHS BEN INT | $7.5M | 196.1K | 0.4% | ▲+9.2% Added · +17K sh | |
| 34 | Alphabet Inc CAP STK CL C | $6.7M | 23.4K | 0.4% | ▲+17% Added · +3K sh | |
| 35 | Berkshire Hathaway Inc Del CL B NEW | $5.7M | 12.0K | 0.3% | ▼−1.1% Reduced · −138 sh | |
| 36 | Palo Alto Networks Inc COM | $5.5M | 34.0K | 0.3% | ▲+157% Added · +21K sh | |
| 37 | McDonalds Corp COM | $4.8M | 15.5K | 0.3% | ▼−17% Reduced · −3K sh | |
| 38 | Tesla Inc COM | $4.6M | 12.3K | 0.3% | ▼−3.2% Reduced · −411 sh | |
| 39 | Schwab Charles Corp COM | $4.4M | 46.4K | 0.3% | ▲+46% Added · +15K sh | |
| 40 | Arista Networks Inc COM SHS | $4.3M | 35.0K | 0.2% | ▲New New position | |
| 41 | Exxon Mobil Corp COM | $4.1M | 23.9K | 0.2% | ▲+3.1% Added · +715 sh | |
| 42 | Wells Fargo & Co COM | $3.7M | 46.9K | 0.2% | ▲+136% Added · +27K sh | |
| 43 | Berkshire Hathaway Inc Del CL A | $3.6M | 5 | 0.2% | —Held | |
| 44 | Chevron Corporation COM | $3.5M | 16.9K | 0.2% | ▲+77% Added · +7K sh | |
| 45 | Autodesk Inc COM | $3.4M | 14.4K | 0.2% | ▲+0.8% Added · +112 sh | |
| 46 | Ishares TR CORE MSCI TOTAL | $3.3M | 38.6K | 0.2% | ▲+22% Added · +7K sh | |
| 47 | Visa Inc COM CL A | $3.1M | 10.2K | 0.2% | ▼−94% Reduced · −164K sh | |
| 48 | Eli Lilly & Co COM | $2.7M | 2.9K | 0.2% | ▲+105% Added · +1K sh | |
| 49 | Ishares Inc MSCI WORLD ETF | $2.7M | 14.7K | 0.2% | ▼−2.6% Reduced · −396 sh | |
| 50 | Abbvie Inc COM | $2.2M | 10.3K | 0.1% | ▲+9.7% Added · +903 sh |
As-of date vs the date the SEC received each filing
| Quarter | As of | Filed | Positions | Value | Form |
|---|---|---|---|---|---|
| Q1 2026 | Mar 31, 2026 | Apr 30, 2026 | 148 | $1.7B | 13F-HR |
| Q4 2025 | Dec 31, 2025 | Feb 9, 2026 | 129 | $1.7B | 13F-HR |
| Q3 2025 | Sep 30, 2025 | Nov 13, 2025 | 129 | $1.9B | 13F-HR |
| Q2 2025 | Jun 30, 2025 | Aug 5, 2025 | 115 | $1.6B | 13F-HR |
| Q1 2025 | Mar 31, 2025 | Apr 30, 2025 | 101 | $1.5B | 13F-HR |
| Q4 2024 | Dec 31, 2024 | Feb 7, 2025 | 110 | $1.6B | 13F-HR |
| Q3 2024 | Sep 30, 2024 | Nov 12, 2024 | 109 | $1.6B | 13F-HR |
| Q2 2024 | Jun 30, 2024 | Jul 29, 2024 | 103 | $1.5B | 13F-HR |
| Q1 2024 | Mar 31, 2024 | May 1, 2024 | 107 | $1.5B | 13F-HR |
| Q4 2023 | Dec 31, 2023 | Jan 30, 2024 | 106 | $1.2B | 13F-HR |
| Q3 2023 | Sep 30, 2023 | Nov 3, 2023 | 91 | $970.6M | 13F-HR |
| Q2 2023 | Jun 30, 2023 | Aug 8, 2023 | 93 | $627.4M | 13F-HR |
| Q1 2023 | Mar 31, 2023 | May 1, 2023 | 91 | $506.4M | 13F-HR |
| Q4 2022 | Dec 31, 2022 | Feb 6, 2023 | 98 | $410.7M | 13F-HR |
| Q3 2022 | Sep 30, 2022 | Nov 14, 2022 | 97 | $454.0M | 13F-HR |
| Q2 2022 | Jun 30, 2022 | Aug 12, 2022 | 86 | $381.4M | 13F-HR |
| Q1 2022 | Mar 31, 2022 | May 5, 2022 | 116 | $1.1B | 13F-HR |
| Q4 2021 | Dec 31, 2021 | Feb 9, 2022 | 141 | $1.3B | 13F-HR |
| Q3 2021 | Sep 30, 2021 | Nov 12, 2021 | 137 | $1.1B | 13F-HR |
| Q2 2021 | Jun 30, 2021 | Aug 6, 2021 | 143 | $1.2B | 13F-HR |
| Q1 2021 | Mar 31, 2021 | May 7, 2021 | 127 | $1.1B | 13F-HR |
| Q4 2020 | Dec 31, 2020 | Feb 12, 2021 | 126 | $929.8M | 13F-HR |
| Q3 2020 | Sep 30, 2020 | Nov 10, 2020 | 109 | $785.3M | 13F-HR |
| Q2 2020 | Jun 30, 2020 | Jul 29, 2020 | 97 | $637.2M | 13F-HR |
Holdings from SEC EDGAR 13F-HR filings, updated quarterly ~45 days after quarter-end. Public domain. The book and weighting are long equity only; disclosed put/call options are listed separately and excluded from those totals. Price-derived performance is withheld until the price-source policy and freshness gate are green.