Featured 13F manager
Shannon River Fund Management LLC Spencer Waxman
New York, NY 21 processed 13Fs on this site · 2021 Q3–2026 Q2
- $1.1B
- 37 Positions
- 2026 Q2
- +113.7% QoQ
- Top 5 29.1%
Spencer Waxman files Shannon River Fund Management LLC as a Form 13F. The latest book is 2026 Q2 at $1.1B, up 113.7% QoQ, led by Tower Semiconductor, Flextronics, and Advanced Micro Devices.
Portfolio
top 5 29.1% · top 10 49.6%
- TSEM - Tower Semiconductor 8.9%
- FLEX - Flextronics 5.5%
- AMD - Advanced Micro Devices 5.5%
- IDCC - Interdigital 4.7%
- CLS - Celestica 4.5%
- COHR - Coherent 4.5%
- HNGE — · CL A 4.2%
- EXTR - Extreme Networks 4.1%
- KLIC - Kulicke & Soffa Inds 4.0%
- TWLO - Twilio · CL A 3.7%
- CIEN - Ciena 3.6%
- LYV - Live Nation 3.5%
- Other 43.3%
AUM over time
Book
| TSEM - Tower Semiconductor | 16.88% | Reduce −16.4% | 504,239 | $175.48 | $88M | −98,565 | +$18M |
| MRVL - Marvell Technology | 10.65% | Add +49.2% | 563,573 | $99.05 | $56M | +185,889 | +$24M |
| LYV - Live Nation | 8.57% | Add +15.3% | 294,398 | $152.51 | $45M | +38,965 | +$8M |
| ABNB - Airbnb · CL A | 5.95% | New | 247,006 | $126.28 | $31M | +247,006 | +$31M |
| RMBS - Rambus Del | 5.48% | New | 333,817 | $86.03 | $29M | +333,817 | +$29M |
| COHR - Coherent | 4.00% | Reduce −47.7% | 87,905 | $238.21 | $21M | −80,013 | −$10M |
| FLEX - Flextronics Intl | 3.89% | Reduce −0.7% | 311,223 | $65.46 | $20M | −2,050 | +$1M |
| AXON - Axon Enterprise | 3.84% | Add +129.0% | 47,442 | $424.69 | $20M | +26,726 | +$8M |
| EXTR - Extreme Networks | 3.78% | Reduce −31.1% | 1,313,061 | $15.08 | $20M | −591,467 | −$12M |
| TOST - Toast · CL A | 3.70% | New | 732,027 | $26.51 | $19M | +732,027 | +$19M |
| LGN - Legence · CL A | 3.64% | Add +0.8% | 337,638 | $56.46 | $19M | +2,775 | +$5M |
| IDCC - Interdigital | 3.12% | Add +1.1% | 54,104 | $302.00 | $16M | +614 | −$691K |
| HNGE — · CL A | 3.07% | Add +78.8% | 417,182 | $38.56 | $16M | +183,828 | +$5M |
| ADTN - Adtran | 2.93% | New | 1,219,976 | $12.58 | $15M | +1,219,976 | +$15M |
| CLS - Celestica | 2.88% | Reduce −50.1% | 53,495 | $281.68 | $15M | −53,635 | −$17M |
| FFIV - F5 | 2.77% | New | 50,196 | $289.33 | $15M | +50,196 | +$15M |
| LION - Lionsgate Studios | 1.90% | New | 1,040,934 | $9.59 | $10M | +1,040,934 | +$10M |
| GWRE - Guidewire Software | 1.79% | Reduce −50.1% | 62,863 | $149.56 | $9M | −63,194 | −$16M |
| UUUU - Energy Fuels | 1.77% | New | 507,555 | $18.25 | $9M | +507,555 | +$9M |
| SPHR - Sphere Entertainment · CL A | 1.64% | New | 73,345 | $117.40 | $9M | +73,345 | +$9M |
| AMBA - Ambarella | 1.13% | Reduce −61.8% | 114,940 | $51.47 | $6M | −186,153 | −$15M |
| APP - Applovin · CL A | 1.10% | New | 14,480 | $398.00 | $6M | +14,480 | +$6M |
| DLR - Digital Rlty Tr | 1.03% | New | 29,838 | $180.21 | $5M | +29,838 | +$5M |
| ALAB - Astera Labs | 0.99% | Reduce −71.7% | 47,394 | $109.60 | $5M | −120,247 | −$23M |
| OSIS - OSI Systems | 0.98% | New | 19,274 | $265.51 | $5M | +19,274 | +$5M |
| EQIX - Equinix | 0.95% | New | 5,102 | $980.24 | $5M | +5,102 | +$5M |
| PLTR - Palantir Technologies · CL A | 0.81% | Add +0.6% | 29,150 | $146.28 | $4M | +185 | −$884K |
| SNOW - Snowflake | 0.76% | New | 26,377 | $150.82 | $4M | +26,377 | +$4M |
Exits / last held
not current holdings · last reported size, unchanged · gone vs 2025 Q4
| Stock | % of portfolio | Recent activity | Shares | Reported price* | Value | Share change | $ change |
|---|---|---|---|---|---|---|---|
| Pegasystems | 9.73% | Exit | 0 | $59.72 | $62M | −1,038,832 | −$62M |
| U - Unity Software | 7.38% | Exit | 0 | $44.17 | $47M | −1,065,452 | −$47M |
| CWAN — · CL A | 4.68% | Exit | 0 | $24.12 | $30M | −1,236,412 | −$30M |
| NCNO - Ncino | 4.57% | Exit | 0 | $25.64 | $29M | −1,135,922 | −$29M |
| KLAC - Klaviyo | 3.72% | Exit | 0 | $32.47 | $24M | −729,703 | −$24M |
| CRDO - Credo Technology | 3.38% | Exit | 0 | $143.89 | $22M | −149,966 | −$22M |
| DOCU - Docusign | 1.68% | Exit | 0 | $68.40 | $11M | −156,813 | −$11M |
| CCC — | 1.34% | Exit | 0 | $7.95 | $9M | −1,075,546 | −$9M |
| QCOM - Qualcomm | 1.24% | Exit | 0 | $171.06 | $8M | −46,212 | −$8M |
| MU - Micron Technology | 0.91% | Exit | 0 | $285.39 | $6M | −20,400 | −$6M |
| WIX — | 0.76% | Exit | 0 | $103.89 | $5M | −46,731 | −$5M |
Filings history
20 periods · normalized AUM · open a period for holdings
| Period | Holdings | AUM | QoQ | Form | Filed | Filing ID |
|---|---|---|---|---|---|---|
| 2026 Q2 | 37 | $1.1B | +113.7% | 13F-HR | 8/13/2026 | 000101359426000886 |
| 2026 Q1 | 28 | $524M | −17.9% | 13F-HR | 5/14/2026 | 000101359426000581 |
| 2025 Q4 | 26 | $638M | +2.7% | 13F-HR | 2/17/2026 | 000101359426000239 |
| 2025 Q3 | 20 | $621M | −17.4% | 13F-HR | 11/13/2025 | 000101359425001398 |
| 2025 Q2 | 24 | $752M | +96.3% | 13F-HR | 8/13/2025 | 000101359425000992 |
| 2025 Q1 | 14 | $383M | −43.5% | 13F-HR | 5/14/2025 | 000101359425000645 |
| 2024 Q4 | 19 | $678M | −5.2% | 13F-HR | 2/13/2025 | 000101359425000260 |
| 2024 Q3 | 19 | $715M | +15.3% | 13F-HR | 11/13/2024 | 000101359424000941 |
| 2024 Q2 | 22 | $620M | +38.1% | 13F-HR | 8/13/2024 | 000101359424000640 |
| 2024 Q1 | 18 | $449M | −17.9% | 13F-HR | 5/14/2024 | 000101359424000471 |
| 2023 Q4 | 23 | $547M | +8.7% | 13F-HR | 2/13/2024 | 000101359424000153 |
| 2023 Q3 | 16 | $503M | +25.4% | 13F-HR | 11/13/2023 | 000101359423000910 |
| 2023 Q2 | 15 | $401M | −9.5% | 13F-HR | 8/11/2023 | 000101359423000659 |
| 2023 Q1 | 27 | $443M | +8.6% | 13F-HR | 5/12/2023 | 000101359423000466 |
| 2022 Q4 | 30 | $408M | +75.1% | 13F-HR | 2/13/2023 | 000101359423000174 |
| 2022 Q3 | 30 | $233M | −33.8% | 13F-HR | 11/14/2022 | 000156761922019714 |
| 2022 Q2 | 35 | $352M | −60.9% | 13F-HR | 8/15/2022 | 000156761922016018 |
| 2022 Q1 | 48 | $901M | — | RESTATEMENT | 7/20/2022 | 000156761922014249 |
| 2022 Q1 | 48 | $901M | −8.6% | 13F-HR | 5/16/2022 | 000156761922010783 |
| 2021 Q4 | 45 | $986M | −30.5% | 13F-HR | 2/14/2022 | 000156761922003912 |
| 2021 Q3 | 57 | $1.4B | — | 13F-HR | 11/15/2021 | 000156761921020217 |
About
Shannon River Fund Management LLC
21 processed 13Fs on this site · 2021 Q3–2026 Q2