Telemark Asset Management, LLC is an SEC-registered investment adviser based in Boston, MA that reports managing 1 hedge fund on Form ADV. It reports $1.1 billion in regulatory assets under management. Its private funds, of all types, hold $1.1 billion in gross assets. Its disclosed U.S. stock holdings returned an estimated +23.4% 2026 YTD through Jun 30 (S&P 500: +9.5%), based on 13F filings. Over a longer period they returned an estimated +34.7% from Q3 2024 to Q2 2026, compared with +37.2% for the S&P 500, based on 13F filings.
- Regulatory assets under management
- $1.1 billionForm ADV Item 5.F
- Gross assets of private funds
- $1.1 billionAll private fund types, Form ADV
- Hedge funds managed
- 11 private funds in total
- Employees
- 3Form ADV Item 5.A
- Registration
- SEC-registered adviserCRD 156770
- Latest Form ADV
- 03/09/2026Disciplinary disclosures: none reported
Estimated 13F portfolio performance
Estimated by AltMountain, derived from the firm’s public Form 13F filings. Not reported by the firm and not the return of any fund.
| Quarter | Est. 13F return | S&P 500 |
|---|---|---|
| Q2 2026 | +20.9% | +14.8% |
| Q1 2026 | +2.0% | -4.6% |
| Q4 2025 | -2.6% | +2.4% |
| Q3 2025 | +9.6% | +7.8% |
| Q2 2025 | +21.0% | +10.4% |
| Q1 2025 | -13.7% | -4.5% |
| Q4 2024 | -0.7% | +2.1% |
| Q3 2024 | -1.3% | +5.4% |
Estimate of the firm's disclosed long U.S. stock portfolio from its quarterly 13F filings, holding each quarter-end portfolio to the next quarter-end at prices implied by all 13F filers. It is a price return before dividends and fees, ignores shorts, options, bonds, cash and trading within the quarter, and is not the return of any fund. Disclosures
Manager of this firm? Report your fund’s actual net return, or email hello@altmountain.com to correct or remove this estimate. Removal requests from the firm are honored.
13F holdings as of Sep 30, 2026
The 50 largest of 58 share positions ($1,394,347,691) reported by Telemark Asset Management, LLC on Form 13F for the quarter ended Sep 30, 2026, filed Nov 10, 2026. Shown as filed with the SEC. Original filing on SEC.gov ↗ The estimated return above runs through Jun 30, 2026; it is updated when the SEC publishes its complete data for the quarter.
| Stock | Value | % of 13F portfolio | Shares | Shares vs prior quarter |
|---|---|---|---|---|
| Nvidia Corporation | $137,028,000 | 9.83% | 600,000 | Unchanged |
| Moderna Inc | $96,285,000 | 6.91% | 500,000 | +7.14% |
| Cameco Corp | $69,336,000 | 4.97% | 800,000 | -11.11% |
| Novanta Inc | $60,430,750 | 4.33% | 425,000 | Unchanged |
| Palantir Technologies Inc | $56,115,000 | 4.02% | 300,000 | +20.00% |
| Andersen Group Inc | $54,128,000 | 3.88% | 995,000 | +99.00% |
| Amazon Com Inc | $49,830,000 | 3.57% | 200,000 | Unchanged |
| Heico Corp New | $42,445,200 | 3.04% | 140,000 | Unchanged |
| Meta Platforms Inc | $36,259,000 | 2.60% | 50,000 | +66.67% |
| Franco Nev Corp | $35,716,500 | 2.56% | 150,000 | +50.00% |
| Kopin Corp | $32,200,000 | 2.31% | 7,000,000 | Unchanged |
| Taiwan Semiconductor Manufac | $31,933,300 | 2.29% | 70,000 | -30.00% |
| Clean Harbors Inc | $31,023,000 | 2.22% | 100,000 | Unchanged |
| Waste Connections Inc | $30,786,000 | 2.21% | 200,000 | Unchanged |
| SLB Limited | $29,232,000 | 2.10% | 600,000 | Unchanged |
| Heico Corp New | $28,541,250 | 2.05% | 125,000 | Unchanged |
| Analog Devices Inc | $27,769,700 | 1.99% | 70,000 | Unchanged |
| Texas Instrs Inc | $22,407,200 | 1.61% | 80,000 | Unchanged |
| Allient Inc | $22,320,000 | 1.60% | 200,000 | Unchanged |
| Halliburton Co | $22,260,000 | 1.60% | 700,000 | -41.67% |
| Baker Hughes Company | $21,960,000 | 1.57% | 400,000 | Unchanged |
| Garmin LTD | $21,513,000 | 1.54% | 75,000 | Unchanged |
| Vertex Pharmaceuticals Inc | $20,912,400 | 1.50% | 40,000 | New |
| Microsoft Corp | $20,516,000 | 1.47% | 40,000 | New |
| Twilio Inc | $20,472,200 | 1.47% | 70,000 | +40.00% |
| Snowflake Inc | $20,373,600 | 1.46% | 60,000 | New |
| Digitalocean Hldgs Inc | $19,608,330 | 1.41% | 147,000 | -26.50% |
| Teradyne Inc | $18,040,950 | 1.29% | 45,000 | -40.00% |
| Alphabet Inc | $17,204,000 | 1.23% | 50,000 | Unchanged |
| Trimble Inc | $17,133,000 | 1.23% | 300,000 | +50.00% |
| Biodesix Inc | $16,102,950 | 1.15% | 539,824 | +10.21% |
| Ligand Pharmaceuticals Inc | $15,618,500 | 1.12% | 50,000 | New |
| Shopify Inc | $14,830,000 | 1.06% | 100,000 | +11.11% |
| Karooooo LTD | $13,509,000 | 0.97% | 225,150 | +4.65% |
| Verisk Analytics Inc | $13,428,000 | 0.96% | 80,000 | New |
| Servicenow Inc | $13,401,000 | 0.96% | 100,000 | New |
| Almonty Inds Inc | $13,160,000 | 0.94% | 1,000,000 | -16.67% |
| Axon Enterprise Inc | $12,675,600 | 0.91% | 30,000 | +50.00% |
| American Superconductor Corp | $11,644,000 | 0.84% | 400,000 | -33.33% |
| Ovintiv Inc | $11,564,000 | 0.83% | 200,000 | +100.00% |
| Imax Corp | $10,960,000 | 0.79% | 200,000 | New |
| Patterson-uti Energy Inc | $10,920,000 | 0.78% | 1,000,000 | +100.00% |
| Codexis Inc | $10,906,511 | 0.78% | 7,846,411 | +103.99% |
| Appian Corp | $10,581,000 | 0.76% | 300,000 | New |
| Lightpath Technologies Inc | $10,567,750 | 0.76% | 1,025,000 | Unchanged |
| Mongodb Inc | $10,458,300 | 0.75% | 30,000 | New |
| Brightview Hldgs Inc | $10,000,000 | 0.72% | 1,000,000 | +17.65% |
| Hillman Solutions Corp | $8,737,500 | 0.63% | 1,250,000 | +13.64% |
| U S Physical Therapy | $8,573,000 | 0.61% | 100,000 | New |
| Corning Inc | $7,688,000 | 0.55% | 50,000 | -69.70% |
Changes since Jun 30, 2026
Comparing the share counts in the two quarter-end filings: 13 new positions, 12 sold out, 16 increased, 10 reduced and 19 unchanged.
New positions
| Stock | Value | Shares |
|---|---|---|
| Vertex Pharmaceuticals Inc | $20,912,400 | 40,000 |
| Microsoft Corp | $20,516,000 | 40,000 |
| Snowflake Inc | $20,373,600 | 60,000 |
| Ligand Pharmaceuticals Inc | $15,618,500 | 50,000 |
| Verisk Analytics Inc | $13,428,000 | 80,000 |
| Servicenow Inc | $13,401,000 | 100,000 |
| Imax Corp | $10,960,000 | 200,000 |
| Appian Corp | $10,581,000 | 300,000 |
| Mongodb Inc | $10,458,300 | 30,000 |
| U S Physical Therapy | $8,573,000 | 100,000 |
| Bioventus Inc | $5,452,000 | 400,000 |
| Lantronix Inc | $4,326,000 | 600,000 |
| Evolv Technologies Hldngs In | $3,255,000 | 700,000 |
Sold out
| Stock | Value at Jun 30, 2026 | Shares held then |
|---|---|---|
| Caterpillar Inc | $31,947,000 | 30,000 |
| Asml Hldg NV | $19,894,400 | 10,000 |
| Modine MFG Co | $18,691,400 | 70,000 |
| Lam Research Corp | $17,333,200 | 40,000 |
| Old Dominion Freight Line In | $15,162,000 | 70,000 |
| D-wave Quantum Inc | $11,995,000 | 500,000 |
| Nextpower Inc | $11,914,000 | 100,000 |
| Applovin Corp | $10,304,600 | 20,000 |
| Ormat Technologies Inc | $8,712,000 | 80,000 |
| Flex LTD | $8,103,500 | 50,000 |
| Knight-swift Transn Hldgs In | $7,787,000 | 100,000 |
| Helios Technologies Inc | $4,462,500 | 50,000 |
Largest increases
| Stock | Change in shares | Change | Value now | Shares now |
|---|---|---|---|---|
| Andersen Group Inc | +495,000 | +99.00% | $54,128,000 | 995,000 |
| Meta Platforms Inc | +20,000 | +66.67% | $36,259,000 | 50,000 |
| Franco Nev Corp | +50,000 | +50.00% | $35,716,500 | 150,000 |
| Palantir Technologies Inc | +50,000 | +20.00% | $56,115,000 | 300,000 |
| Moderna Inc | +33,333 | +7.14% | $96,285,000 | 500,000 |
| Twilio Inc | +20,000 | +40.00% | $20,472,200 | 70,000 |
| Ovintiv Inc | +100,000 | +100.00% | $11,564,000 | 200,000 |
| Trimble Inc | +100,000 | +50.00% | $17,133,000 | 300,000 |
| Codexis Inc | +4,000,000 | +103.99% | $10,906,511 | 7,846,411 |
| Patterson-uti Energy Inc | +500,000 | +100.00% | $10,920,000 | 1,000,000 |
| Axon Enterprise Inc | +10,000 | +50.00% | $12,675,600 | 30,000 |
| Brightview Hldgs Inc | +150,000 | +17.65% | $10,000,000 | 1,000,000 |
| Biodesix Inc | +50,000 | +10.21% | $16,102,950 | 539,824 |
| Shopify Inc | +10,000 | +11.11% | $14,830,000 | 100,000 |
| Hillman Solutions Corp | +150,000 | +13.64% | $8,737,500 | 1,250,000 |
| Karooooo LTD | +10,000 | +4.65% | $13,509,000 | 225,150 |
Largest reductions
| Stock | Change in shares | Change | Value now | Shares now |
|---|---|---|---|---|
| Corning Inc | -115,000 | -69.70% | $7,688,000 | 50,000 |
| Halliburton Co | -500,000 | -41.67% | $22,260,000 | 700,000 |
| Taiwan Semiconductor Manufac | -30,000 | -30.00% | $31,933,300 | 70,000 |
| Teradyne Inc | -30,000 | -40.00% | $18,040,950 | 45,000 |
| Cameco Corp | -100,000 | -11.11% | $69,336,000 | 800,000 |
| Applied Matls Inc | -15,000 | -50.00% | $7,670,700 | 15,000 |
| Digitalocean Hldgs Inc | -53,000 | -26.50% | $19,608,330 | 147,000 |
| American Superconductor Corp | -200,000 | -33.33% | $11,644,000 | 400,000 |
| BWX Technologies Inc | -30,000 | -37.50% | $6,850,000 | 50,000 |
| Almonty Inds Inc | -200,000 | -16.67% | $13,160,000 | 1,000,000 |
Each list shows up to 20 positions, largest first by dollar amount. Changes compare two quarter-end snapshots, with the earlier share count adjusted for stock splits AltMountain detected. They do not show when, or at what price, anything was bought or sold.
From public Form 13F filings, not verified. Form 13F is filed up to 45 days after the quarter ends, so positions may have changed. It lists only certain long positions in U.S.-listed stocks and exchange-traded funds; options are not shown here, and short positions, most bonds, cash, non-U.S. securities and private investments are not reported at all, so a holding may be one side of a hedge. A filing covers the manager as a whole, not any single fund, and filings contain errors. This is not investment advice or a recommendation to buy or sell any security. Disclosures
Hedge funds filing Form D (1)
Matched to this firm by the fund names and related persons in each Form D. The list may be incomplete.
Private funds reported on Form ADV (1)
As reported in the adviser's Form ADV filed Mar 5, 2024. Funds also listed from Form D are shown above.
From SEC filings. Firm data comes from the SEC's Form ADV data as of Oct 2, 2026; performance estimates come from Form 13F. AltMountain has not verified this information, and it is not an offer, solicitation or recommendation. Full disclosures