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 | 13.66% | Add +45.2% | 1,833,336 | $33.45 | $61M | +570,610 | +$23M |
| WIX — | 11.25% | Reduce −21.4% | 367,563 | $137.48 | $51M | −99,931 | −$7M |
| CGNX - Cognex | 9.40% | New | 994,862 | $42.42 | $42M | +994,862 | +$42M |
| NVDA - Nvidia | 9.30% | Add +13.6% | 46,214 | $903.56 | $42M | +5,522 | +$22M |
| IDCC - Interdigital | 8.74% | Reduce −22.0% | 368,809 | $106.46 | $39M | −103,998 | −$12M |
| FLEX - Flextronics | 7.28% | Add +2.9% | 1,143,269 | $28.61 | $33M | +31,746 | −$1M |
| Informatica · CL A | 7.01% | Add +0.5% | 899,146 | $35.00 | $31M | +4,218 | +$6M |
| TALK - Talkspace | 5.42% | Add +36.4% | 6,819,103 | $3.57 | $24M | +1,819,103 | +$12M |
| EQIX - Equinix | 4.91% | New | 26,741 | $825.33 | $22M | +26,741 | +$22M |
| CWAN — · CL A | 4.12% | Add +84.2% | 1,045,914 | $17.69 | $19M | +478,048 | +$7M |
| GWRE - Guidewire Software | 3.39% | New | 130,532 | $116.71 | $15M | +130,532 | +$15M |
| APPN - Appian · CL A | 3.29% | New | 369,977 | $39.95 | $15M | +369,977 | +$15M |
| DT - Dynatrace | 3.09% | Reduce −2.7% | 298,432 | $46.44 | $14M | −8,330 | −$3M |
| TDC - Teradata Del | 2.26% | New | 262,471 | $38.67 | $10M | +262,471 | +$10M |
| AKAM - Akamai Technologies | 2.13% | New | 88,035 | $108.76 | $10M | +88,035 | +$10M |
| GTM - Zoominfo Technologies | 2.01% | New | 562,632 | $16.03 | $9M | +562,632 | +$9M |
| Squarespace · CLASS A | 1.63% | New | 200,600 | $36.44 | $7M | +200,600 | +$7M |
| GLBE - Global E Online | 1.11% | Add +342.3% | 137,523 | $36.35 | $5M | +106,431 | +$4M |
Exits / last held
not current holdings · last reported size, unchanged · gone vs 2023 Q4
| Stock | % of portfolio | Recent activity | Shares | Reported price* | Value | Share change | $ change |
|---|---|---|---|---|---|---|---|
| CLS - Celestica | 6.74% | Exit | 0 | $29.28 | $37M | −1,259,755 | −$37M |
| SFM - Sprout Social · CL A | 3.04% | Exit | 0 | $61.44 | $17M | −270,825 | −$17M |
| VSTS - Vestis | 2.56% | Exit | 0 | $21.14 | $14M | −662,205 | −$14M |
| GDDY - Godaddy · CL A | 2.34% | Exit | 0 | $106.16 | $13M | −120,849 | −$13M |
| AMD - Advanced Micro Devices | 0.81% | Exit | 0 | $147.41 | $4M | −29,998 | −$4M |
| Z - Zillow Group · CL A | 0.80% | Exit | 0 | $56.72 | $4M | −77,294 | −$4M |
| PTC - PTC Inc | 0.61% | Exit | 0 | $174.98 | $3M | −19,168 | −$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