13F Insight
DOSSIER · 13F-HR · Q2 2026

Portolan Capital Management, LLC

$2.7B in tracked AUM across 148 positions as of Q2 2026.

PC
CIK 0001350290 · last filed Jun 30, 2026
Total AUM
$2.7B
as of Q2 2026
Holdings
148
−7 QoQ
positions
Whale Score
54
54
tracked
Activity
201
+49 new, −56 sold
changes this Q
AI Analysis · Q2 2026

Portolan Capital Management, LLC filed its latest 13F-HR for Q2 2026. 201 position changes this quarter — 49 new, 56 exited, 49 added, 47 trimmed.

Quarter at a glance — Q2 2026

201 material changes this filing.

ADD
VPGVISHAY PRECISION GROUP INC
+130K sh
+$117M
5.7%
ADD
VIRTVIRTU FINL INC
+1.8M sh
+$115M
4.8%
ADD
QLYSQUALYS INC
+478K sh
+$66M
2.7%
TRIM
CSTLCASTLE BIOSCIENCES INC
-1.4M sh
$-59M
0.3%
NEW
PENGPENGUIN SOLUTIONS INC
+546K sh
+$42M
1.6%
ADD
MECMAYVILLE ENGR CO INC
+786K sh
+$39M
1.8%
ADD
ENVAENOVA INTL INC
+101K sh
+$32M
1.8%

Top 10 holdings

By portfolio weight as of Q2 2026. Source: SEC EDGAR 13F-HR filings.

#HoldingValueSharesWeight
01
VPG
VISHAY PRECISION GROUP INC
$151M1.0M5.7%02
VIRT
VIRTU FINL INC
$128M2.1M4.8%03
TTMI
TTM TECHNOLOGIES INC
$95M508K3.6%04
MOD
MODINE MFG CO
$84M314K3.1%05
QLYS
QUALYS INC
$73M530K2.7%06
FOUR
SHIFT4 PMTS INC
$54M1.1M2.0%07
MEC
MAYVILLE ENGR CO INC
$49M1.3M1.8%08
ENVA
ENOVA INTL INC
$48M199K1.8%09
SMTC
SEMTECH CORP
$48M295K1.8%10
CLS
CELESTICA INC
$46M127K1.7%

Filing history

2026Q2Jun 30
$2.7B▲ 43.1%
148 positionsView →2025Q4Dec 31
$1.9B▲ 52.0%
155 positionsView →2025Q3Sep 30
$1.2B▲ 15.7%
79 positionsLocked2025Q2Jun 30
$1.1B▼ 19.3%
73 positionsLocked2025Q1Mar 31
$1.3B▼ 11.5%
109 positionsLocked2024Q4Dec 31
$1.5B▲ 7.8%
131 positionsLocked2024Q3Sep 30
$1.4B▲ 13.6%
129 positionsLocked2024Q2Jun 30
$1.2B▼ 7.5%
117 positionsLocked2024Q1Mar 31
$1.3B▲ 14.8%
116 positionsLocked2023Q4Dec 31
$1.1B▲ 6.9%
127 positionsLocked2023Q3Sep 30
$1.1B▼ 5.3%
123 positionsLocked2023Q2Jun 30
$1.1B▲ 7.6%
120 positionsLocked
Showing 12 of 51