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 | 15.18% | Reduce −6.2% | 3,691,439 | $14.47 | $53M | −243,370 | −$20M |
| MANH - Manhattan Associates | 11.58% | Reduce −23.9% | 355,674 | $114.60 | $41M | −111,533 | −$24M |
| DT - Dynatrace | 9.60% | Reduce −32.6% | 856,898 | $39.44 | $34M | −414,791 | −$26M |
| NICE — | 9.11% | Add +4.0% | 166,564 | $192.45 | $32M | +6,380 | −$3M |
| Alteryx · CL A | 5.91% | New | 429,922 | $48.42 | $21M | +429,922 | +$21M |
| RMBS - Rambus Del | 5.56% | Add +16.5% | 910,556 | $21.49 | $20M | +128,701 | −$5M |
| IDCC - Interdigital | 5.16% | Reduce −37.3% | 298,531 | $60.80 | $18M | −177,358 | −$12M |
| FIVN - FIVE9 | 5.11% | Reduce −9.3% | 197,332 | $91.14 | $18M | −20,206 | −$6M |
| Holding | 4.81% | Reduce −21.9% | 1,148,829 | $14.74 | $17M | −322,360 | −$12M |
| SONO - Sonos | 4.26% | Reduce −24.9% | 831,982 | $18.04 | $15M | −275,732 | −$16M |
| Holding · CL A | 3.62% | Hold | 1,275,351 | $9.99 | $13M | — | — |
| WMG - Warner Music Group · CL A | 3.20% | Reduce −44.3% | 462,501 | $24.36 | $11M | −367,735 | −$20M |
| Knowbe4 · CL A | 2.97% | Add +74.2% | 668,286 | $15.62 | $10M | +284,631 | +$2M |
| GTM - Zoominfo Technologies · CL A | 2.63% | Reduce −55.6% | 278,490 | $33.24 | $9M | −348,132 | −$28M |
| AMBA - Ambarella | 2.62% | Add +93.2% | 140,656 | $65.46 | $9M | +67,870 | +$2M |
| MTCH - Match Group | 2.50% | Reduce −26.5% | 126,300 | $69.69 | $9M | −45,500 | −$10M |
| Pegasystems | 1.54% | Reduce −72.2% | 113,124 | $47.84 | $5M | −293,165 | −$27M |
| Macondray Cap Acquisitn | 1.35% | Hold | 475,000 | $9.97 | $5M | — | — |
| Taboola | 0.80% | New | 1,109,002 | $2.53 | $3M | +1,109,002 | +$3M |
| Holding | 0.70% | Hold | 250,000 | $9.80 | $2M | — | — |
| Holding · CL A | 0.56% | Hold | 200,000 | $9.85 | $2M | — | — |
| Silicon Laboratories | 0.55% | Reduce −52.6% | 13,914 | $140.22 | $2M | −15,424 | −$2M |
| Ironsource · CL A | 0.13% | New | 186,500 | $2.38 | $444K | +186,500 | +$444K |
| Class Acceleration | 0.01% | Hold | 5,000 | $9.80 | $49K | — | — |
| Innovid | 0.01% | Hold | 20,000 | $1.65 | $33K | — | — |
| Holding | 0.00% | Hold | 1,000 | $10.00 | $10K | — | — |
Exits / last held
not current holdings · last reported size, unchanged · gone vs 2022 Q1
| Stock | % of portfolio | Recent activity | Shares | Reported price* | Value | Share change | $ change |
|---|---|---|---|---|---|---|---|
| NYT - New York Times · CL A | 5.81% | Exit | 0 | $45.84 | $52M | −1,143,070 | −$52M |
| DOCN - Digitalocean | 3.44% | Exit | 0 | $57.85 | $31M | −535,888 | −$31M |
| UBER - UBER Technologies | 3.14% | Exit | 0 | $35.68 | $28M | −792,843 | −$28M |
| Elastic | 2.81% | Exit | 0 | $88.95 | $25M | −284,287 | −$25M |
| FLYW - Flywire | 2.11% | Exit | 0 | $30.58 | $19M | −622,474 | −$19M |
| Farfetch · CL A | 2.01% | Exit | 0 | $15.12 | $18M | −1,197,429 | −$18M |
| GDDY - Godaddy · CL A | 2.01% | Exit | 0 | $83.70 | $18M | −216,282 | −$18M |
| IAC - Iac Interactivecorp | 1.63% | Exit | 0 | $1.16 | $15M | −12,606,559 | −$15M |
| V - VISA · CL A | 1.27% | Exit | 0 | $221.77 | $11M | −51,536 | −$11M |
| ADSK - Autodesk | 1.20% | Exit | 0 | $214.36 | $11M | −50,369 | −$11M |
| SFM - Sprout Social · CL A | 1.00% | Exit | 0 | $80.12 | $9M | −112,011 | −$9M |
| Cascade Acquisition · CL A | 0.56% | Exit | 0 | $10.08 | $5M | −501,966 | −$5M |
| Zendesk | 0.39% | Exit | 0 | $120.29 | $4M | −29,520 | −$4M |
| Instructure | 0.35% | Exit | 0 | $20.06 | $3M | −158,353 | −$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