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
| FLEX - Flextronics | 21.96% | Reduce −16.9% | 3,069,370 | $16.66 | $51M | −622,069 | −$2M |
| NICE — | 12.28% | Reduce −8.8% | 151,980 | $188.24 | $29M | −14,584 | −$3M |
| CRM - Salesforce | 8.68% | New | 140,464 | $143.84 | $20M | +140,464 | +$20M |
| RMBS - Rambus Del | 8.08% | Reduce −18.7% | 739,988 | $25.42 | $19M | −170,568 | −$758K |
| MANH - Manhattan Associates | 7.71% | Reduce −62.0% | 134,988 | $133.03 | $18M | −220,686 | −$23M |
| GTM - Zoominfo Technologies · CL A | 7.04% | Add +41.4% | 393,680 | $41.66 | $16M | +115,190 | +$7M |
| FIVN - FIVE9 | 5.08% | Reduce −20.1% | 157,696 | $74.98 | $12M | −39,636 | −$6M |
| Alteryx · CL A | 4.58% | Reduce −55.6% | 190,970 | $55.84 | $11M | −238,952 | −$10M |
| UBER - UBER Technologies | 4.47% | New | 392,928 | $26.50 | $10M | +392,928 | +$10M |
| CGNX - Cognex | 4.41% | New | 247,727 | $41.45 | $10M | +247,727 | +$10M |
| WMG - Warner Music Group · CL A | 3.45% | Reduce −25.3% | 345,696 | $23.21 | $8M | −116,805 | −$3M |
| MTCH - Match Group | 2.99% | Add +15.6% | 146,049 | $47.75 | $7M | +19,749 | −$2M |
| Kornit Digital | 2.65% | New | 231,634 | $26.61 | $6M | +231,634 | +$6M |
| Macondray Cap Acquisitn | 2.04% | Hold | 475,000 | $10.01 | $5M | — | — |
| AMBA - Ambarella | 1.96% | Reduce −42.3% | 81,173 | $56.18 | $5M | −59,483 | −$5M |
| Holding | 1.06% | Hold | 250,000 | $9.88 | $2M | — | — |
| Holding · CL A | 0.85% | Hold | 200,000 | $9.95 | $2M | — | — |
| TSLA - Tesla | 0.24% | New | 2,100 | $265.24 | $557K | +2,100 | +$557K |
| Taboola | 0.19% | Reduce −77.6% | 248,339 | $1.81 | $449K | −860,663 | −$2M |
| Innovid | 0.02% | Hold | 20,000 | $2.70 | $54K | — | — |
| Class Acceleration | 0.02% | Hold | 5,000 | $9.80 | $49K | — | — |
| Holding | 0.00% | Hold | 1,000 | $10.00 | $10K | — | — |
Exits / last held
not current holdings · last reported size, unchanged · gone vs 2022 Q2
| Stock | % of portfolio | Recent activity | Shares | Reported price* | Value | Share change | $ change |
|---|---|---|---|---|---|---|---|
| DT - Dynatrace | 9.60% | Exit | 0 | $39.44 | $34M | −856,898 | −$34M |
| IDCC - Interdigital | 5.16% | Exit | 0 | $60.80 | $18M | −298,531 | −$18M |
| Holding | 4.81% | Exit | 0 | $14.74 | $17M | −1,148,829 | −$17M |
| SONO - Sonos | 4.26% | Exit | 0 | $18.04 | $15M | −831,982 | −$15M |
| Holding · CL A | 3.62% | Exit | 0 | $9.99 | $13M | −1,275,351 | −$13M |
| Knowbe4 · CL A | 2.97% | Exit | 0 | $15.62 | $10M | −668,286 | −$10M |
| Pegasystems | 1.54% | Exit | 0 | $47.84 | $5M | −113,124 | −$5M |
| Silicon Laboratories | 0.55% | Exit | 0 | $140.22 | $2M | −13,914 | −$2M |
| Ironsource · CL A | 0.13% | Exit | 0 | $2.38 | $444K | −186,500 | −$444K |
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