Portolan Capital Management, LLC

In its 13F for Q2 2024 (holdings as of June 30, 2024, filed August 14, 2024), Portolan Capital Management, LLC reported 117 stock positions worth $1.2 billion. Its top holding was Lantheus (LNTH) at 4.2% of the portfolio, followed by Celestica (CLS, 3.6%) and Super Micro Computer (SMCI, 2.9%). Compared with Q1 2024, it opened 21 new positions, sold out of 20, added to 36 and reduced 59. The biggest buy was Lantheus (LNTH, shares +20%) and the biggest sale Bio-Rad Laboratories-A (BIO, shares −72%).

Most Recent 13F
Q2 2026
Location
BOSTON, MA
CIK
0001350290
Portfolio Value
$1.2B (Q2 2024)
SEC Filing
0001104659-24-089663 ↗ filed Aug 14, 2024

Holdings Value

0$1.0B$2.0B$3.0B Q1 2024: $1.3B Q1 2024 Q2 2024: $1.2B $1.2B Q2 2024 Q3 2024: $1.4B Q3 2024 Q4 2024: $1.5B Q4 2024 Q1 2025: $1.3B Q1 2025 Q2 2025: $1.6B Q2 2025 Q3 2025: $1.8B Q3 2025 Q4 2025: $1.9B Q4 2025 Q1 2026: $1.9B Q1 2026 Q2 2026: $2.7B Q2 2026

Holdings 117 stocks · $1.2B
LNTH Lantheus Holdings Inc. 4.18% 632,105 $50.8M Add +20.2%
CLS Celestica Inc. 3.56% 753,116 $43.2M Reduce -24.7%
SMCI Super Micro Computer Inc. 2.86% 42,439 $34.8M Reduce -5.9%
ZETA Zeta Global Holdings Corp. Class A 2.79% 1,919,190 $33.9M Reduce -18.3%
KTOS Kratos Defense & Security 2.69% 1,630,421 $32.6M Add +2.9%
ELF Elf Beauty Inc. 2.42% 139,649 $29.4M Reduce -16.2%
MOD Modine Manufacturing Co. 2.30% 278,825 $27.9M Add +3.7%
WDC Western Digital Corp. 2.22% 355,997 $27.0M Reduce -5.1%
NVT Nvent Electric PLC 2.20% 348,556 $26.7M Add +22.2%
CSTL Castle Biosciences Inc. 2.17% 1,210,952 $26.4M Add +16.1%
QTRX Quanterix Corp. 2.09% 1,918,030 $25.3M Add +65.0%
HNST The Honest Co. Inc. 1.95% 8,105,357 $23.7M Add +8.2%
TTMI TTM Technologies 1.91% 1,192,680 $23.2M Add +130.3%
BLFS Biolife Solutions Inc. 1.77% 1,004,228 $21.5M Add +15.2%
ACMR Acm Research Inc. Class A 1.63% 855,835 $19.7M Add +59.0%
NTRA Natera Inc. 1.49% 166,577 $18.0M Reduce -17.2%
UTHR United Therapeutics Corp. 1.44% 54,845 $17.5M Reduce -50.6%
KMPR Kemper Corp. 1.40% 286,316 $17.0M Add +95.9%
MU Micron Technology Inc. 1.31% 121,103 $15.9M Reduce -24.2%
GENI Genius Sports Ltd. 1.30% 2,898,346 $15.8M Add +31.5%
TGLS Tecnoglass Holdings Inc. 1.21% 293,587 $14.7M Reduce -19.8%
AIG American International Group 1.19% 195,168 $14.5M Add +53.5%
IIIV I3 Verticals Inc. Class A 1.14% 629,151 $13.9M Reduce -32.0%
SIMO Silicon Motion Technol-ADR 1.14% 170,246 $13.8M Add +6.4%
FOUR SHIFT4 Payments Inc. Class A 1.13% 187,500 $13.8M Reduce -21.6%
MRVI Maravai Lifesciences Hldgs-A 1.09% 1,846,140 $13.2M Add +171.3%
CDMO Avid Bioservices Inc. 1.07% 1,820,779 $13.0M Add +110.0%
SKX Skechers USA Inc. Class A 1.04% 183,190 $12.7M Reduce -14.4%
SG Sweetgreen Inc. Class A 1.04% 419,875 $12.7M Reduce -57.9%
INDI Indie Semiconductor Inc. Class A 1.04% 2,040,951 $12.6M Add +10.7%
DELL Dell Technologies -C 1.02% 89,992 $12.4M Add +51.1%
CLBT Cellebrite Di Ltd. 1.00% 1,020,952 $12.2M Reduce -10.7%
QNST Quinstreet Inc. 1.00% 731,285 $12.1M Add +102.8%
ORN Orion Group Holdings Inc. 0.99% 1,267,822 $12.1M New
META Meta Platforms Inc. Class A 0.98% 23,661 $11.9M Reduce -6.9%
RDDT Reddit Inc. Class A 0.98% 186,046 $11.9M New
KRUS Kura Sushi USA Inc. Class A 0.98% 187,875 $11.9M Add +26.3%
ARCT Arcturus Therapeutics Holdin 0.97% 484,907 $11.8M Add +98.2%
PHAT Phathom Pharmaceuticals Inc. 0.96% 1,130,089 $11.6M New
CELH Celsius Holdings Inc. 0.92% 196,493 $11.2M Add +98.0%
AVAV Aerovironment Inc. 0.92% 61,280 $11.2M Add +32.5%
AEM Agnico Eagle Mines Ltd. 0.91% 169,030 $11.1M Reduce -45.8%
SMWB Similarweb Ltd. 0.87% 1,367,259 $10.6M Reduce -33.0%
FLEX Flex Ltd. 0.87% 356,839 $10.5M Reduce -17.1%
ORCL Oracle Corp. 0.84% 72,110 $10.2M Add +37.8%
PENG Penguin Solutions Inc. filed as SMART GLOBAL HLDGS INC 0.83% 441,815 $10.1M Reduce -36.3%
NOG Northern Oil and Gas Inc. 0.82% 267,170 $9.9M Reduce -10.0%
IESC Ies Holdings Inc. filed as IES HLDGS INC 0.80% 69,455 $9.7M New
PAYO Payoneer Global Inc. 0.77% 1,677,402 $9.3M Add +38.4%
CROX Crocs Inc. 0.76% 63,373 $9.2M Reduce -52.4%
BASE Couchbase Inc. 0.74% 491,944 $9.0M Reduce -16.7%
VRT Vertiv Holdings Co. Class A 0.73% 102,466 $8.9M Reduce -21.1%
GTES Gates Industrial Corp. UK Ltd. 0.73% 558,192 $8.8M Add +157.2%
AU Anglogold Ashanti PLC 0.69% 331,286 $8.3M Reduce -38.5%
MITK Mitek Systems Inc. 0.68% 742,728 $8.3M New
TECK Teck Resources Ltd.-CLS B 0.63% 158,961 $7.6M New
ENVA Enova International Inc. 0.63% 122,081 $7.6M Reduce -1.2%
RPAY Repay Holdings Corp. 0.62% 715,111 $7.6M Reduce -12.3%
BIDU Baidu Inc. - Spon ADR 0.60% 84,847 $7.3M Reduce -55.9%
STNG Scorpio Tankers Inc. 0.60% 90,006 $7.3M Reduce -24.4%
LUXE Luxexperience BV filed as MYT NETHERLANDS PARENT B V 0.58% 1,382,816 $7.1M Add +94.2%
EGO Eldorado Gold Corp. 0.57% 472,142 $7.0M Reduce -17.9%
AAOI Applied Optoelectronics Inc. 0.57% 841,059 $7.0M Reduce -41.4%
BIO Bio-Rad Laboratories-A 0.57% 25,150 $6.9M Reduce -72.4%
SLM SLM Corp. 0.55% 318,697 $6.6M Add +688.5%
MXCT Maxcyte Inc. 0.54% 1,687,650 $6.6M Reduce -2.0%
MDU Mdu Resources Group Inc. 0.54% 262,014 $6.6M New
INFN Infinera Corp. 0.54% 1,077,664 $6.6M New
BV Brightview Holdings Inc. 0.53% 485,165 $6.5M Reduce -32.6%
TTWO Take-Two Interactive Softwre 0.53% 41,384 $6.4M Reduce -40.1%
STKL Sunopta Inc. 0.53% 1,183,964 $6.4M Reduce -47.8%
PRIM Primoris Services Corp. 0.52% 126,542 $6.3M New
VRN Veren Inc. 0.51% 791,988 $6.2M Add +1.9%
OPRA Opera Ltd.-ADR 0.50% 435,464 $6.1M New
RDNT Radnet Inc. 0.49% 101,347 $6.0M Add +7.8%
PBPB Potbelly Corp. 0.49% 741,766 $6.0M Reduce -35.3%
INSW International Seaways Inc. 0.45% 93,191 $5.5M Reduce -9.3%
AKAM Akamai Technologies Inc. 0.44% 59,716 $5.4M New
HDL Super Hi International Holdi 0.44% 296,540 $5.3M New
KIDS Orthopediatrics Corp. 0.44% 185,329 $5.3M New
CTOS Custom Truck One Source Inc. 0.42% 1,186,380 $5.2M Reduce -4.7%
NMM Navios Maritime Partners LP 0.42% 101,090 $5.2M Add +2.2%
AOSL Alpha & Omega Semiconductor 0.42% 137,995 $5.2M New
NVGS Navigator Holdings Ltd. 0.41% 287,156 $5.0M Reduce -7.1%
WRBY Warby Parker Inc. Class A 0.40% 302,898 $4.9M Reduce -69.7%
EXTR Extreme Networks Inc. 0.40% 360,104 $4.8M New
FORR Forrester Research Inc. 0.37% 264,877 $4.5M Reduce -33.0%
APLD Applied Digital Corp. 0.37% 756,556 $4.5M Reduce -37.3%
TLS Telos Corporation 0.37% 1,110,557 $4.5M Add +50.6%
WKME Walkme Ltd. 0.36% 313,839 $4.4M Reduce -86.2%
INVE Inve Technologies Inc. filed as IDENTIV INC 0.36% 1,014,886 $4.4M Reduce -29.6%
AMPH Amphastar Pharmaceuticals Inc. 0.36% 108,863 $4.4M Add +19.6%
ALT Altimmune Inc. 0.35% 640,242 $4.3M Reduce -27.8%
VKTX Viking Therapeutics Inc. 0.35% 79,422 $4.2M Reduce -18.6%
OTLY Oatly Group AB 0.34% 4,384,079 $4.1M New
LMB Limbach Holdings Inc. 0.34% 72,352 $4.1M New
AMKR Amkor Technology Inc. 0.32% 98,394 $3.9M New
HDSN Hudson Technologies Inc. 0.32% 442,896 $3.9M Reduce -35.4%
PCRX Pacira Biosciences Inc. 0.31% 131,901 $3.8M New
MTRX Matrix Service Co. 0.31% 379,070 $3.8M Reduce -47.6%
BELFB Bel Fuse Inc. Class B 0.29% 54,237 $3.5M Reduce -49.6%
GENK Gen Restaurant Group Inc. 0.27% 366,118 $3.3M Add +0.1%
SKY Champion Homes Inc. filed as SKYLINE CHAMPION CORPORATION 0.25% 44,426 $3.0M Reduce -44.9%
DIBS 1STDIBS.COM Inc. 0.24% 660,953 $3.0M Add +1.0%
EVER Everquote Inc. Class A 0.24% 140,232 $2.9M Reduce -61.8%
MSFT Microsoft Corp. 0.20% 5,300 $2.4M Reduce -0.0%
OPK Opko Health Inc. 0.19% 1,886,749 $2.4M Reduce -41.8%
MAMA Mama's Creations Inc. 0.19% 344,024 $2.3M New
WEX Wex Inc. 0.19% 12,863 $2.3M New
RELY Remitly Global Inc. 0.18% 179,892 $2.2M Add +2.3%
SMTC Semtech Corp. 0.16% 64,182 $1.9M Reduce -61.3%
CWST Casella Waste Systems Inc. Class A 0.13% 15,682 $1.6M Reduce -0.1%
GOOG Alphabet Inc. Class C 0.09% 6,171 $1.1M Reduce -0.0%
ICAD Icad Inc. 0.07% 653,372 $849K Reduce -45.9%
BXC Bluelinx Holdings Inc. 0.03% 4,229 $394K No change
NRDY Nerdy Inc. 0.00% 32,100 $54K Reduce -98.9%
HBIO Harvard Bioscience Inc. 0.00% 12,000 $34K Reduce -98.3%

Portfolio Sells Q1 2024 → Q2 2024
BIO Bio-Rad Laboratories-A Reduce -72.4% 0.57% −1.83
WKME Walkme Ltd. Reduce -86.2% 0.36% −1.13
RCM R1 RCM Inc. Sold out 0.00% −1.08
AAOI Applied Optoelectronics Inc. Reduce -41.4% 0.57% −0.94
BIDU Baidu Inc. - Spon ADR Reduce -55.9% 0.60% −0.94
SG Sweetgreen Inc. Class A Reduce -57.9% 1.04% −0.88
GDS GDS Holdings Ltd. - ADR Sold out 0.00% −0.84
CROX Crocs Inc. Reduce -52.4% 0.76% −0.70
RPRX Royalty Pharma PLC Class A Sold out 0.00% −0.67
STKL Sunopta Inc. Reduce -47.8% 0.53% −0.66
NRDY Nerdy Inc. Reduce -98.9% 0.00% −0.64
WRBY Warby Parker Inc. Class A Reduce -69.7% 0.40% −0.63
SMCI Super Micro Computer Inc. Reduce -5.9% 2.86% −0.60
PBPB Potbelly Corp. Reduce -35.3% 0.49% −0.57
AXTI Axt Inc. Sold out 0.00% −0.56
PENG Penguin Solutions Inc. Reduce -36.3% 0.83% −0.56
SMWB Similarweb Ltd. Reduce -33.0% 0.87% −0.52
INVE Inve Technologies Inc. Reduce -29.6% 0.36% −0.51
AEM Agnico Eagle Mines Ltd. Reduce -45.8% 0.91% −0.51
UTHR United Therapeutics Corp. Reduce -50.6% 1.44% −0.50
GFL GFL Environmental Inc.-Sub VT Sold out 0.00% −0.50
IIIV I3 Verticals Inc. Class A Reduce -32.0% 1.14% −0.47
BASE Couchbase Inc. Reduce -16.7% 0.74% −0.44
TTGT Techtarget Holdings Inc. Sold out 0.00% −0.41
MTRX Matrix Service Co. Reduce -47.6% 0.31% −0.41
CYRX Cryoport Inc. Sold out 0.00% −0.40
DOCN Digitalocean Holdings Inc. Sold out 0.00% −0.38
OVERSEAS SHIPHOLDING GROUP-A Sold out 0.00% −0.38
NVEI Nuvei Corp.-Subordinate VTG Sold out 0.00% −0.37
UCTT Ultra Clean Holdings Inc. Sold out 0.00% −0.35
ALT Altimmune Inc. Reduce -27.8% 0.35% −0.34
AZZ Azz Inc. Sold out 0.00% −0.30
EVER Everquote Inc. Class A Reduce -61.8% 0.24% −0.28
FORR Forrester Research Inc. Reduce -33.0% 0.37% −0.28
ALRM Alarm.com Holdings Inc. Sold out 0.00% −0.28
SKY Champion Homes Inc. Reduce -44.9% 0.25% −0.27
DOUG Douglas Elliman Inc. Sold out 0.00% −0.27
VKTX Viking Therapeutics Inc. Reduce -18.6% 0.35% −0.26
HDSN Hudson Technologies Inc. Reduce -35.4% 0.32% −0.25
TTWO Take-Two Interactive Softwre Reduce -40.1% 0.53% −0.25
TGLS Tecnoglass Holdings Inc. Reduce -19.8% 1.21% −0.24
AU Anglogold Ashanti PLC Reduce -38.5% 0.69% −0.23
HBIO Harvard Bioscience Inc. Reduce -98.3% 0.00% −0.22
PRCH Porch Group Inc. Sold out 0.00% −0.21
BELFB Bel Fuse Inc. Class B Reduce -49.6% 0.29% −0.20
SMTC Semtech Corp. Reduce -61.3% 0.16% −0.19
LTRX Lantronix Inc. Sold out 0.00% −0.16
CTOS Custom Truck One Source Inc. Reduce -4.7% 0.42% −0.13
MU Micron Technology Inc. Reduce -24.2% 1.31% −0.12
BV Brightview Holdings Inc. Reduce -32.6% 0.53% −0.12

Portfolio Buys Q1 2024 → Q2 2024
LNTH Lantheus Holdings Inc. Add +20.2% 4.18% +1.69
TTMI TTM Technologies Add +130.3% 1.91% +1.29
ORN Orion Group Holdings Inc. New 0.99% +0.99
RDDT Reddit Inc. Class A New 0.98% +0.98
PHAT Phathom Pharmaceuticals Inc. New 0.96% +0.96
IESC Ies Holdings Inc. New 0.80% +0.80
KMPR Kemper Corp. Add +95.9% 1.40% +0.71
MITK Mitek Systems Inc. New 0.68% +0.68
MRVI Maravai Lifesciences Hldgs-A Add +171.3% 1.09% +0.64
CDMO Avid Bioservices Inc. Add +110.0% 1.07% +0.63
TECK Teck Resources Ltd.-CLS B New 0.63% +0.63
NVT Nvent Electric PLC Add +22.2% 2.20% +0.56
MDU Mdu Resources Group Inc. New 0.54% +0.54
BLFS Biolife Solutions Inc. Add +15.2% 1.77% +0.54
INFN Infinera Corp. New 0.54% +0.54
PRIM Primoris Services Corp. New 0.52% +0.52
QNST Quinstreet Inc. Add +102.8% 1.00% +0.51
DELL Dell Technologies -C Add +51.1% 1.02% +0.50
OPRA Opera Ltd.-ADR New 0.50% +0.50
SLM SLM Corp. Add +688.5% 0.55% +0.48
KTOS Kratos Defense & Security Add +2.9% 2.69% +0.47
AKAM Akamai Technologies Inc. New 0.44% +0.44
HDL Super Hi International Holdi New 0.44% +0.44
KIDS Orthopediatrics Corp. New 0.44% +0.44
AIG American International Group Add +53.5% 1.19% +0.44
GTES Gates Industrial Corp. UK Ltd. Add +157.2% 0.73% +0.43
ACMR Acm Research Inc. Class A Add +59.0% 1.63% +0.43
AOSL Alpha & Omega Semiconductor New 0.42% +0.42
CSTL Castle Biosciences Inc. Add +16.1% 2.17% +0.41
LUXE Luxexperience BV Add +94.2% 0.58% +0.41
EXTR Extreme Networks Inc. New 0.40% +0.40
AVAV Aerovironment Inc. Add +32.5% 0.92% +0.38
MOD Modine Manufacturing Co. Add +3.7% 2.30% +0.35
ARCT Arcturus Therapeutics Holdin Add +98.2% 0.97% +0.34
GENI Genius Sports Ltd. Add +31.5% 1.30% +0.34
OTLY Oatly Group AB New 0.34% +0.34
LMB Limbach Holdings Inc. New 0.34% +0.34
ORCL Oracle Corp. Add +37.8% 0.84% +0.34
AMKR Amkor Technology Inc. New 0.32% +0.32
PAYO Payoneer Global Inc. Add +38.4% 0.77% +0.32
PCRX Pacira Biosciences Inc. New 0.31% +0.31
CELH Celsius Holdings Inc. Add +98.0% 0.92% +0.30
SIMO Silicon Motion Technol-ADR Add +6.4% 1.14% +0.20
MAMA Mama's Creations Inc. New 0.19% +0.19
WEX Wex Inc. New 0.19% +0.19
RDNT Radnet Inc. Add +7.8% 0.49% +0.14
TLS Telos Corporation Add +50.6% 0.37% +0.13
NMM Navios Maritime Partners LP Add +2.2% 0.42% +0.10
AMPH Amphastar Pharmaceuticals Inc. Add +19.6% 0.36% +0.05
INDI Indie Semiconductor Inc. Class A Add +10.7% 1.04% +0.04

All Filings

QuarterPositions13F Reported ValueTop Holdings
Q2 2026 148$2.7BVPG, VIRT, TTMI, MOD, QLYS
Q1 2026 144$1.9BMOD, TTMI, CLS, VIRT, AKAM
Q4 2025 155$1.9BTTMI, MOD, CSTL, CLS, AKAM
Q3 2025 119$1.8BMOD, TTMI, ELF, DBRG, CLS
Q2 2025 118$1.6BCLS, KTOS, ELF, AVAV, MOD
Q1 2025 109$1.3BLNTH, SLM, KTOS, GENI, MOD
Q4 2024 131$1.5BLNTH, CLS, SMTC, MOD, HNST
Q3 2024 129$1.4BLNTH, ZETA, KTOS, TLN, CLS
Q2 2024 117$1.2BLNTH, CLS, SMCI, ZETA, KTOS
Q1 2024 116$1.3BSMCI, CLS, LNTH, ELF, BIO