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
| Pegasystems | 10.98% | Add +1.3% | 798,356 | $93.20 | $74M | +9,989 | +$17M |
| IDCC - Interdigital | 10.91% | Reduce −19.2% | 381,645 | $193.72 | $74M | −90,507 | +$7M |
| MRVL - Marvell Technology | 10.63% | Reduce −6.4% | 652,207 | $110.45 | $72M | −44,597 | +$22M |
| TSEM - Tower Semiconductor | 8.25% | Reduce −18.9% | 1,085,891 | $51.51 | $56M | −252,324 | −$3M |
| CWAN — · CL A | 7.57% | Reduce −23.9% | 1,862,813 | $27.52 | $51M | −585,966 | −$11M |
| FLEX - Flextronics | 5.72% | Reduce −21.0% | 1,009,056 | $38.39 | $39M | −268,205 | −$4M |
| PYPL - Paypal | 3.39% | Reduce −3.4% | 269,470 | $85.35 | $23M | −9,430 | +$1M |
| BL - Blackline | 2.93% | New | 326,313 | $60.76 | $20M | +326,313 | +$20M |
| GPN - Global Pmts | 2.62% | New | 158,356 | $112.06 | $18M | +158,356 | +$18M |
| CART - Maplebear | 2.53% | Reduce −6.0% | 414,065 | $41.42 | $17M | −26,271 | −$789K |
| Informatica · CL A | 2.38% | Reduce −61.1% | 622,431 | $25.93 | $16M | −979,372 | −$24M |
| Confluent · CLASS A | 1.48% | New | 359,019 | $27.96 | $10M | +359,019 | +$10M |
| GWRE - Guidewire Software | 1.48% | Reduce −62.6% | 59,532 | $168.58 | $10M | −99,539 | −$19M |
| TALK - Talkspace | 1.47% | Reduce −34.1% | 3,226,598 | $3.09 | $10M | −1,672,757 | −$269K |
| NATL - Ncr Atleos | 1.47% | New | 293,000 | $33.92 | $10M | +293,000 | +$10M |
| DOCU - Docusign | 0.13% | New | 10,000 | $89.94 | $899K | +10,000 | +$899K |
Exits / last held
not current holdings · last reported size, unchanged · gone vs 2024 Q3
| Stock | % of portfolio | Recent activity | Shares | Reported price* | Value | Share change | $ change |
|---|---|---|---|---|---|---|---|
| WIX — | 6.93% | Exit | 0 | $167.17 | $50M | −296,411 | −$50M |
| CGNX - Cognex | 6.06% | Exit | 0 | $40.50 | $43M | −1,068,933 | −$43M |
| ADBE - Adobe | 5.61% | Exit | 0 | $517.78 | $40M | −77,379 | −$40M |
| CLS - Celestica | 3.96% | Exit | 0 | $51.12 | $28M | −553,425 | −$28M |
| DT - Dynatrace | 3.75% | Exit | 0 | $53.47 | $27M | −501,536 | −$27M |
| Squarespace · CLASS A | 1.72% | Exit | 0 | $46.43 | $12M | −264,360 | −$12M |
| UTI - Universal Technical Inst | 0.47% | Exit | 0 | $16.26 | $3M | −207,722 | −$3M |
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