Similarweb
SMWB
97 hedge funds and large institutions have $372M invested in Similarweb in 2025 Q4 according to their latest regulatory filings, with 19 funds opening new positions, 29 increasing their positions, 31 reducing their positions, and 13 closing their positions.
46% more first-time investments, than exits
New positions opened: 19 | Existing positions closed: 13
4.77% more ownership
Funds ownership: 53.88% → 58.64% (+4.8%)
3% more funds holding
Funds holding: 94 → 97 (+3)
0% more funds holding in top 10
Funds holding in top 10: 4 → 4 (0)
6% less repeat investments, than reductions
Existing positions increased: 29 | Existing positions reduced: 31
12% less capital invested
Capital invested by funds: $426M → $372M (-$53.2M)
90% less call options, than puts
Call options by funds: $543K | Put options by funds: $5.62M
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
PF
Phoenix Financial
Givatayim,
Israel
|
+$10.4M |
| 2 |
MMH
Menora Mivtachim Holdings
Ramat Gan,
Israel
|
+$6.51M |
| 3 |
Wellington Management Group
Boston,
Massachusetts
|
+$4.38M |
| 4 |
UBS Group
Zurich,
Switzerland
|
+$1.8M |
| 5 |
PAP
Persistent Asset Partners
Hong Kong
|
+$1.45M |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
PCM
Portolan Capital Management
Boston,
Massachusetts
|
-$5.53M |
| 2 |
SGM
Scalar Gauge Management
Dallas,
Texas
|
-$4.11M |
| 3 |
EIM
Essex Investment Management
Boston,
Massachusetts
|
-$3.54M |
| 4 |
CI
Ceera Investments
Bellaire,
Texas
|
-$2.97M |
| 5 |
Susquehanna International Group
Bala Cynwyd,
Pennsylvania
|
-$2.6M |
SMWB Hedge Fund Activity: Q4 2025 in Review
97 of the 8,228 institutional investors tracked by Wall St. Rank reported a position in Similarweb (SMWB) for Q4 2025, worth a combined $372M — down 12% from $426M a quarter earlier.
Buyers outnumbered sellers: 19 funds opened new SMWB positions and 13 closed out — a net gain of 6 holders — while 29 added to existing stakes and 31 trimmed.
The largest buyer was Phoenix Financial, adding an estimated $10.4M. The largest seller was Portolan Capital Management, cutting an estimated $5.53M.
- 97 institutional investors held Similarweb (SMWB) as of Q4 2025, up from 94 in Q3 2025.
- Funds reported $372M of Similarweb stock for Q4 2025, down 12% quarter-over-quarter.
- 19 funds opened new Similarweb positions in Q4 2025 and 13 closed out, a net change of +6 holders.
- The largest Similarweb buyer in Q4 2025 was Phoenix Financial, an estimated $10.4M added.
- The largest Similarweb seller in Q4 2025 was Portolan Capital Management, an estimated $5.53M sold.
Based on aggregated 13F filings for Q4 2025.