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
| WIX — | 10.51% | Add +45.0% | 467,494 | $123.02 | $58M | +145,168 | +$28M |
| IDCC - Interdigital | 9.38% | Reduce −26.4% | 472,807 | $108.54 | $51M | −169,458 | −$217K |
| TSEM - Tower Semiconductor | 7.04% | New | 1,262,726 | $30.52 | $39M | +1,262,726 | +$39M |
| CLS - Celestica | 6.74% | Reduce −25.7% | 1,259,755 | $29.28 | $37M | −435,384 | −$5M |
| FLEX - Flextronics | 6.19% | Reduce −25.2% | 1,111,523 | $30.46 | $34M | −375,138 | −$6M |
| Informatica · CL A | 4.64% | Add +10.4% | 894,928 | $28.39 | $25M | +84,537 | +$8M |
| NVDA - Nvidia | 3.68% | Reduce −21.1% | 40,692 | $495.22 | $20M | −10,910 | −$2M |
| DT - Dynatrace | 3.07% | Reduce −34.5% | 306,762 | $54.69 | $17M | −161,726 | −$5M |
| SFM - Sprout Social · CL A | 3.04% | Reduce −4.2% | 270,825 | $61.44 | $17M | −11,905 | +$3M |
| VSTS - Vestis | 2.56% | New | 662,205 | $21.14 | $14M | +662,205 | +$14M |
| GDDY - Godaddy · CL A | 2.34% | Reduce −69.7% | 120,849 | $106.16 | $13M | −278,040 | −$17M |
| TALK - Talkspace | 2.32% | New | 5,000,000 | $2.54 | $13M | +5,000,000 | +$13M |
| CWAN — · CL A | 2.08% | Reduce −5.9% | 567,866 | $20.03 | $11M | −35,679 | −$298K |
| AMD - Advanced Micro Devices | 0.81% | Reduce −79.1% | 29,998 | $147.41 | $4M | −113,473 | −$10M |
| Z - Zillow Group · CL A | 0.80% | New | 77,294 | $56.72 | $4M | +77,294 | +$4M |
| PTC - PTC Inc | 0.61% | New | 19,168 | $174.96 | $3M | +19,168 | +$3M |
| GLBE - Global E Online | 0.23% | New | 31,092 | $39.63 | $1M | +31,092 | +$1M |
Exits / last held
not current holdings · last reported size, unchanged · gone vs 2023 Q3
| Stock | % of portfolio | Recent activity | Shares | Reported price* | Value | Share change | $ change |
|---|---|---|---|---|---|---|---|
| Alteryx · CL A | 4.63% | Exit | 0 | $37.69 | $23M | −618,669 | −$23M |
| MRVL - Marvell Technology | 2.46% | Exit | 0 | $54.13 | $12M | −228,700 | −$12M |
| OKTA - OKTA Inc · CL A | 1.59% | Exit | 0 | $81.51 | $8M | −98,000 | −$8M |
| ACIW - Aci Worldwide | 0.39% | Exit | 0 | $22.57 | $2M | −87,789 | −$2M |
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