Q2 2026 13F · SEC CIK 1125725

Gagnon Securities LLC

Wealth managerFiled 2026-08-05 for Q2 2026. Open the filing ↗ · All SEC filings ↗

Reported 13F value: $518.8M
Reported positions: 83
Top holdings a year, 3 yrs: +19.4%
Assets under management: $529.7M

Gagnon Securities LLC is a wealth manager that reported 83 positions worth $518.8M in its Q2 2026 13F, filed 2026-08-05. Its largest holdings were CareDx, Inc. (CDNA, 9.7%), Genedx Holdings Corp (WGS, 6.9%), Ensign Group Inc (ENSG, 5.4%). A portfolio copying its top holdings returned 19.4% a year over the last 3 years, against 20.4% for the S&P 500.

Gagnon Securities LLC holdings largest 50 of 83 positions.

Weights are shares of the filer's total reported 13F value, compared with Q1 2026. Share changes may reflect splits; weight changes also reflect price moves. A 13F shows long US-listed positions only, up to 135 days after the fact.

Gagnon Securities LLC 13F holdings
Stock	% of 13F value	Q1 2026	Shares	Share change	Reported value
CDNACareDx, Inc.	9.7%	7.1%	1,770,735	+0.5%	$50.5M
WGSGenedx Holdings Corp	6.9%	4.5%	524,865	+73.1%	$36.0M
ENSGEnsign Group Inc	5.4%	8.4%	173,911	-3.2%	$27.9M
AMRCAmeresco Inc	4.4%	4.9%	826,562	-1.6%	$22.8M
GNRCGenerac Hldgs Inc	4.1%	3.4%	73,170	-2.3%	$21.4M
EPDEnterprise Prods Partners L	3.6%	4.5%	510,576	-0.7%	$18.8M
QDELQuidelortho Corp	3.5%	1.5%	1,030,371	+155.5%	$18.0M
CAKECheesecake Factory Inc	3.4%	2.8%	221,792	-1.4%	$17.6M
EQIXEquinix Inc	3.4%	3.8%	16,720	-1.4%	$17.4M
KMXCarmax Inc	3.3%	3.0%	325,410	+5.1%	$17.2M
FRSHFreshworks Inc Class A Com	3.0%	3.2%	1,563,866	-9.7%	$15.8M
PCRXPacira Biosciences Inc	3.0%	3.2%	608,617	-1.4%	$15.4M
FIVNFive9 Inc	3.0%	2.2%	722,698	+16.2%	$15.4M
HNGEHinge Health, Inc.	2.9%	1.1%	182,959	+47.3%	$15.2M
BLFSBiolife Solutions Inc	2.9%	2.4%	535,906	-0.1%	$15.1M
PROFProfound Med Corp	2.5%	2.9%	1,960,074	+0.8%	$13.0M
CARGCargurus Inc	2.4%	2.1%	367,073	+35.2%	$12.5M
TMCITreace Med Concepts Inc	2.3%	1.6%	3,029,543	-41.8%	$12.1M
000000000Koninklijke Philips N V	2.3%	—	765,179	—	$11.7M
ISRGIntuitive Surgical Inc	2.2%	3.4%	29,144	-7.8%	$11.6M
BLBlackline Inc	2.0%	2.5%	375,769	+26.8%	$10.5M
ASPNAspen Aerogels Inc	1.9%	1.5%	1,535,812	-17.5%	$9.7M
PRLBProto Labs Inc	1.8%	1.5%	116,283	+4.9%	$9.5M
VERXVertex Inc	1.7%	1.3%	761,026	+62.5%	$8.7M
AMPLAmplitude Inc	1.6%	1.7%	1,055,508	-0.4%	$8.1M
HZOMarinemax Inc	1.5%	1.4%	211,480	-4.1%	$7.7M
OSUROrasure Technologies Inc	1.4%	1.2%	1,592,147	-7.1%	$7.1M
DVDoubleverify Hldgs Inc	1.1%	1.1%	523,328	+7.1%	$5.7M
CELCCelcuity Inc	1.1%	1.4%	53,240	-0.2%	$5.6M
CMGChipotle Mexican Grill Inc	1.0%	1.2%	155,463	-1.5%	$5.3M
CTRECaretrust REIT Inc	1.0%	1.1%	129,955	-2.3%	$5.2M
PNTGPennant Group Inc	1.0%	1.0%	135,035	-1.8%	$5.0M
WCPRFWhitecap Res Inc	0.9%	1.1%	435,100	-0.1%	$4.5M
ICUIIcu Med Inc	0.8%	0.9%	29,400	-1.2%	$4.3M
KLTRKaltura Inc	0.8%	0.9%	3,266,999	-0.4%	$4.2M
MCHPMicrochip Technology Inc.	0.5%	0.4%	26,229	-2.3%	$2.4M
GNTXGentex Corp	0.3%	0.3%	57,159	+0.4%	$1.4M
GNLGlobal Net Lease Inc	0.3%	0.4%	160,598	-5.6%	$1.4M
SLGSl Green Rlty Corp	0.3%	0.2%	25,862	+0.0%	$1.3M
SAMBoston Beer Inc	0.2%	0.4%	7,283	+0.6%	$1.3M
NCNONcino Inc	0.2%	0.3%	75,333	-5.3%	$1.2M
FLGFlagstar Bank National Assoc	0.2%	0.2%	74,456	-0.3%	$1.1M
APPSDigital Turbine Inc	0.2%	—	81,839	—	$1.1M
WEAVWeave Communications Inc	0.2%	—	157,170	—	$999K
DOCUDocusign Inc	0.2%	0.2%	20,906	-1.5%	$929K
CNFCnfinance Hldgs Ltd	0.2%	0.3%	332,345	+5.9%	$921K
GOOGLAlphabet Inc	0.2%	—	2,556	—	$913K
MRVLMarvell Technology Inc	0.2%	—	2,923	—	$871K
TECHBio-Techne Corp	0.2%	—	12,230	—	$864K
DVNDevon Energy Corp New	0.2%	0.2%	19,021	-0.2%	$786K

What Gagnon Securities LLC bought and sold in Q2 2026, against Q1 2026.

New positions

Q1 2026's filing was too long to tell new positions apart.

Share counts compared with the Q1 2026 13F; a split also changes share counts. The latest filing lists more than 50 positions, so a position that left the top 50 may still be held.

How the holdings did against the S&P 500.

1 year: +29.1% /yr; S&P 500 +20.1%
3 years: +19.4% /yr; S&P 500 +20.4%
5 years: +1.9% /yr; S&P 500 +11.6%

A portfolio of the filer's 20 largest 13F positions, weighted by value, bought the trading day after each 13F was filed and held until the next one was: what copying this filer could have earned. 13Fs show long US-listed positions only, so this is an estimate of the stock picks, not the fund's reported returns.

Reported 13F value by quarter.

13F value by quarter
Quarter	13F value	Positions
Q2 2026	$518.8M	83
Q1 2026	$433.2M	85
Q4 2025	$491.1M	86
Q3 2025	$498.5M	86
Q2 2025	$492.4M	87
Q1 2025	$454.5M	98
Q4 2024	$496.3M	91
Q3 2024	$504.4M	102
Q2 2024	$444.0M	97
Q1 2024	$422.5M	98
Q4 2023	$416.6M	102
Q3 2023	$399.1M	97

Questions about Gagnon Securities LLC's portfolio

What stocks does Gagnon Securities LLC own?

Gagnon Securities LLC's latest 13F, for Q2 2026 and filed Aug 5, 2026, lists 83 positions worth $518.8M. The largest are CareDx, Inc. (CDNA) at 9.7%, Genedx Holdings Corp (WGS) at 6.9%, Ensign Group Inc (ENSG) at 5.4%, Ameresco Inc (AMRC) at 4.4% and Generac Hldgs Inc (GNRC) at 4.1%.

What did Gagnon Securities LLC buy last quarter?

In Q2 2026, Gagnon Securities LLC added Quidelortho Corp (QDEL) (+155.5% shares), Genedx Holdings Corp (WGS) (+73.1% shares) and Vertex Inc (VERX) (+62.5% shares), compared with its Q1 2026 filing.

What did Gagnon Securities LLC sell last quarter?

In Q2 2026, Gagnon Securities LLC cut from its top 50 Navigator Holdings PLC (NVGS), cut from its top 50 Ishares Tr (SGOV), cut from its top 50 Alpha & Omega Semiconductor (AOSL), cut from its top 50 Patterson-Uti Energy Inc (PTEN), cut from its top 50 Pfizer Inc (PFE), Treace Med Concepts Inc (TMCI) (-41.8% shares), Aspen Aerogels Inc (ASPN) (-17.5% shares) and Freshworks Inc Class A Com (FRSH) (-9.7% shares), compared with its Q1 2026 filing.

How has Gagnon Securities LLC's portfolio performed?

A portfolio copying Gagnon Securities LLC's 20 largest 13F holdings each quarter, from the day each filing was public, returned +19.4% a year over the last 3 years, against +20.4% for the S&P 500. Over 1 year: +29.1% against +20.1%. Over 5 years: +1.9% a year against +11.6%.

When is Gagnon Securities LLC's next 13F filing due?

13F filings are due 45 days after each quarter ends. Gagnon Securities LLC's filing for the quarter ending Sep 30, 2026 is due by Nov 14, 2026; this page updates the day after it is published.

How much money does Gagnon Securities LLC manage?

Gagnon Securities LLC reported $529.7M of regulatory assets under management on its latest SEC Form ADV. Its 13F, which covers only US-listed stocks and options, totals $518.8M.