GAGNON SECURITIES LLC SEC EDGAR Filings (CIK 0001125725)

SEC EDGAR filings, ownership reports, and insider transactions for GAGNON SECURITIES LLC.

Business address
1370 Avenue Of The Americas, 26 Th Floor, New York, NY, 10019
Top securities (13F)
AL, ENSG, WGS, AMRC, CDNA, FRSH, ISRG, EPD, TMCI, BL, BLFS, EQIX, NVGS, GNRC, CAKE, ASPN, PCRX, CARG, KMX, and EXAS
Top holdings (Schedule 13G)
AMRC, CDNA, PSIX, TMCI, CNF, PROF, and OSUR
State of incorporation
DE
Fiscal year end
31 December
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GAGNON SECURITIES LLC has filed 250 SEC EDGAR filings since 22 Feb 2001

Latest Filings

Recent SEC filings for GAGNON SECURITIES LLC including SCHEDULE 13G, SCHEDULE 13G/A, 13F-HR and more.

Form type Document Filing Description Filing date Reporting date File number(s)
SCHEDULE 13G Open SCHEDULE 13G document View SEC filing for SCHEDULE 13G 17 Nov 2025
SCHEDULE 13G/A Open SCHEDULE 13G/A document View SEC filing for SCHEDULE 13G/A 14 Nov 2025
13F-HR Open 13F-HR document View SEC filing for 13F-HR 03 Nov 2025 30 Sep 2025 028-06377
SCHEDULE 13G/A Open SCHEDULE 13G/A document View SEC filing for SCHEDULE 13G/A 24 Oct 2025
N-PX Open N-PX document View SEC filing for N-PX 05 Aug 2025 30 Jun 2025 028-06377
SCHEDULE 13G Open SCHEDULE 13G document View SEC filing for SCHEDULE 13G 24 Jul 2025
13F-HR Open 13F-HR document View SEC filing for 13F-HR 23 Jul 2025 30 Jun 2025 028-06377
SCHEDULE 13G Open SCHEDULE 13G document View SEC filing for SCHEDULE 13G 15 May 2025
13F-HR Open 13F-HR document View SEC filing for 13F-HR 09 May 2025 31 Mar 2025 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 24 Jan 2025 31 Dec 2024 028-06377
SCHEDULE 13G/A Open SCHEDULE 13G/A document View SEC filing for SCHEDULE 13G/A 23 Jan 2025
SCHEDULE 13G/A Open SCHEDULE 13G/A document View SEC filing for SCHEDULE 13G/A 23 Jan 2025
SCHEDULE 13G/A Open SCHEDULE 13G/A document View SEC filing for SCHEDULE 13G/A 23 Jan 2025
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A 14 Nov 2024
13F-HR Open 13F-HR document View SEC filing for 13F-HR 12 Nov 2024 30 Sep 2024 028-06377
N-PX Open N-PX document View SEC filing for N-PX 29 Aug 2024 30 Jun 2024 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A 21 Aug 2024
13F-HR Open 13F-HR document View SEC filing for 13F-HR 14 Aug 2024 30 Jun 2024 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 13 May 2024 31 Mar 2024 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 14 Feb 2024 31 Dec 2023 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 13 Feb 2024
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 13 Feb 2024
13F-HR Open 13F-HR document View SEC filing for 13F-HR 14 Nov 2023 30 Sep 2023 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 08 Aug 2023 30 Jun 2023 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 10 Apr 2023 31 Mar 2023 028-06377
SC 13G Open SC 13G document View SEC filing for SC 13G SC 13G 13 Mar 2023
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 13 Feb 2023
13F-HR Open 13F-HR document View SEC filing for 13F-HR 07 Feb 2023 31 Dec 2022 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 06 Feb 2023
13F-HR Open 13F-HR document View SEC filing for 13F-HR 14 Nov 2022 30 Sep 2022 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 11 Oct 2022
13F-HR Open 13F-HR document View SEC filing for 13F-HR 01 Aug 2022 30 Jun 2022 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 09 May 2022 31 Mar 2022 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 10 Mar 2022
13F-HR Open 13F-HR document View SEC filing for 13F-HR 08 Feb 2022 31 Dec 2021 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 03 Feb 2022
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 03 Feb 2022
13F-HR Open 13F-HR document View SEC filing for 13F-HR 12 Nov 2021 30 Sep 2021 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 24 Sep 2021
13F-HR Open 13F-HR document View SEC filing for 13F-HR 28 Jul 2021 30 Jun 2021 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 14 May 2021 31 Mar 2021 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 11 May 2021
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 21 Apr 2021
SC 13G Open SC 13G document View SEC filing for SC 13G SCHEDULE 13G 08 Apr 2021
13F-HR Open 13F-HR document View SEC filing for 13F-HR 12 Feb 2021 31 Dec 2020 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 09 Feb 2021
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 09 Feb 2021
13F-HR Open 13F-HR document View SEC filing for 13F-HR 12 Nov 2020 30 Sep 2020 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 13 Aug 2020 30 Jun 2020 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 11 May 2020 31 Mar 2020 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 14 Feb 2020 31 Dec 2019 028-06377
SC 13G Open SC 13G document View SEC filing for SC 13G SC 13G 13 Feb 2020
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 13 Feb 2020
13F-HR Open 13F-HR document View SEC filing for 13F-HR 08 Nov 2019 30 Sep 2019 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 12 Aug 2019 30 Jun 2019 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 20 Jun 2019
13F-HR Open 13F-HR document View SEC filing for 13F-HR 13 May 2019 31 Mar 2019 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 18 Jan 2019
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 18 Jan 2019
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 18 Jan 2019
13F-HR Open 13F-HR document View SEC filing for 13F-HR 18 Jan 2019 31 Dec 2018 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 13 Nov 2018 30 Sep 2018 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 06 Nov 2018
13F-HR Open 13F-HR document View SEC filing for 13F-HR 09 Aug 2018 30 Jun 2018 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 14 Jun 2018
SC 13G Open SC 13G document View SEC filing for SC 13G SCHEDULE 13G 25 May 2018
13F-HR Open 13F-HR document View SEC filing for 13F-HR 09 May 2018 31 Mar 2018 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 13 Feb 2018 31 Dec 2017 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 13 Feb 2018
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 13 Feb 2018
13F-HR/A Open 13F-HR/A document View SEC filing for 13F-HR/A 14 Nov 2017 30 Sep 2017 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 14 Nov 2017 30 Sep 2017 028-06377
SC 13G Open SC 13G document View SEC filing for SC 13G SC 13G 10 Aug 2017
13F-HR Open 13F-HR document View SEC filing for 13F-HR 20 Jul 2017 30 Jun 2017 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 11 May 2017 31 Mar 2017 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 14 Feb 2017 31 Dec 2016 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 14 Feb 2017
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 14 Feb 2017
SC 13G Open SC 13G document View SEC filing for SC 13G SCHEDULE 13G 24 Jan 2017
13F-HR Open 13F-HR document View SEC filing for 13F-HR 14 Nov 2016 30 Sep 2016 028-06377
13F-HR/A Open 13F-HR/A document View SEC filing for 13F-HR/A 24 Aug 2016 30 Jun 2016 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 10 Aug 2016 30 Jun 2016 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 03 May 2016 31 Mar 2016 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 16 Feb 2016 31 Dec 2015 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 12 Feb 2016
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 12 Feb 2016
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 12 Feb 2016
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 12 Feb 2016
SC 13D/A Open SC 13D/A document View SEC filing for SC 13D/A SC 13D/A 03 Feb 2016
SC 13D/A Open SC 13D/A document View SEC filing for SC 13D/A SC 13D/A 28 Oct 2015
13F-HR Open 13F-HR document View SEC filing for 13F-HR 16 Oct 2015 30 Sep 2015 028-06377
SC 13G Open SC 13G document View SEC filing for SC 13G SCHEDULE 13G 23 Sep 2015
SC 13G Open SC 13G document View SEC filing for SC 13G SCHEDULE 13G 12 Aug 2015
13F-HR Open 13F-HR document View SEC filing for 13F-HR 24 Jul 2015 30 Jun 2015 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 27 May 2015
13F-HR Open 13F-HR document View SEC filing for 13F-HR 12 May 2015 31 Mar 2015 028-06377
SC 13G Open SC 13G document View SEC filing for SC 13G SCHEDULE 13G 07 Apr 2015
13F-HR Open 13F-HR document View SEC filing for 13F-HR 13 Feb 2015 31 Dec 2014 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 12 Feb 2015
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 10 Feb 2015
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 03 Feb 2015
SC 13D/A Open SC 13D/A document View SEC filing for SC 13D/A SCHEDULE 13D/A 10 Dec 2014
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 07 Nov 2014
13F-HR Open 13F-HR document View SEC filing for 13F-HR 15 Oct 2014 30 Sep 2014 028-06377
SC 13G Open SC 13G document View SEC filing for SC 13G SCHEDULE 13G 24 Sep 2014
SC 13G Open SC 13G document View SEC filing for SC 13G SCHEDULE 13G 02 Sep 2014
13F-HR Open 13F-HR document View SEC filing for 13F-HR 31 Jul 2014 30 Jun 2014 028-06377
SC 13G Open SC 13G document View SEC filing for SC 13G SCHEDULE 13G 29 Jul 2014
SC 13D/A Open SC 13D/A document View SEC filing for SC 13D/A SCHEDULE 13D/A 26 Jun 2014
SC 13D/A Open SC 13D/A document View SEC filing for SC 13D/A SCHEDULE 13D/A 12 Jun 2014
SC 13D/A Open SC 13D/A document View SEC filing for SC 13D/A SCHEDULE 13D/A 15 May 2014
13F-HR Open 13F-HR document View SEC filing for 13F-HR 06 May 2014 31 Mar 2014 028-06377
SC 13D/A Open SC 13D/A document View SEC filing for SC 13D/A SCHEDULE 13D/A 22 Apr 2014
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 18 Mar 2014
SC 13D/A Open SC 13D/A document View SEC filing for SC 13D/A SCHEDULE 13D/A 05 Mar 2014
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 07 Feb 2014
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 06 Feb 2014
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 06 Feb 2014
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 06 Feb 2014
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SC 13G/A 06 Feb 2014
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 06 Feb 2014
13F-HR/A Open 13F-HR/A document View SEC filing for 13F-HR/A 06 Feb 2014 31 Dec 2013 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 05 Feb 2014
SC 13G Open SC 13G document View SEC filing for SC 13G SCHEDULE 13G 05 Feb 2014
13F-HR Open 13F-HR document View SEC filing for 13F-HR 14 Jan 2014 31 Dec 2013 028-06377
SC 13G Open SC 13G document View SEC filing for SC 13G SCHEDULE 13G 28 Oct 2013
13F-HR Open 13F-HR document View SEC filing for 13F-HR 18 Oct 2013 30 Sep 2013 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR 02 Aug 2013 30 Jun 2013 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 03 Jun 2013
SC 13D/A Open SC 13D/A document View SEC filing for SC 13D/A SCHEDULE 13D/A 25 Apr 2013
13F-HR Open 13F-HR document View SEC filing for 13F-HR GAG 25 Apr 2013 31 Mar 2013 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 13 Feb 2013
SC 13G Open SC 13G document View SEC filing for SC 13G SCHEDULE 13G 13 Feb 2013
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 13 Feb 2013
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 13 Feb 2013
SC 13G Open SC 13G document View SEC filing for SC 13G SCHEDULE 13G 13 Feb 2013
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 13 Feb 2013
SC 13G Open SC 13G document View SEC filing for SC 13G SCHEDULE 13G 13 Feb 2013
13F-HR Open 13F-HR document View SEC filing for 13F-HR GAG 18 Jan 2013 31 Dec 2012 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR GAG 06 Nov 2012 30 Sep 2012 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR GAG 15 Aug 2012 30 Jun 2012 028-06377
SC 13G Open SC 13G document View SEC filing for SC 13G NDQ 08 May 2012
13F-HR Open 13F-HR document View SEC filing for 13F-HR GAG 01 May 2012 31 Mar 2012 028-06377
SC 13D Open SC 13D document View SEC filing for SC 13D SCHEDULE 13D 05 Apr 2012
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 08 Feb 2012
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 08 Feb 2012
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 07 Feb 2012
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 07 Feb 2012
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A SCHEDULE 13G/A 30 Jan 2012
13F-HR Open 13F-HR document View SEC filing for 13F-HR GAG 26 Jan 2012 31 Dec 2011 028-06377
13F-HR/A Open 13F-HR/A document View SEC filing for 13F-HR/A GAG 14 Nov 2011 30 Sep 2011 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR GAG 25 Oct 2011 30 Sep 2011 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR GAGNON 29 Jul 2011 30 Jun 2011 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR GAGNON 02 May 2011 31 Mar 2011 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A RTI 06 Apr 2011
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A STARLIMS 14 Feb 2011
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A REGEN 14 Feb 2011
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A 14 Feb 2011
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A XFONE 14 Feb 2011
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A VRAD 14 Feb 2011
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A CYTORI 14 Feb 2011
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A RTI 11 Feb 2011
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A PLX 11 Feb 2011
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A DELIA 11 Feb 2011
SC 13G Open SC 13G document View SEC filing for SC 13G DURECT 11 Feb 2011
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A CVD 11 Feb 2011
SC 13G Open SC 13G document View SEC filing for SC 13G RUDOLPH 11 Feb 2011
13F-HR Open 13F-HR document View SEC filing for 13F-HR 04 Feb 2011 31 Dec 2010 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR GAGNON SECURITIES 02 Nov 2010 30 Sep 2010 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR GAGNON SECURITIES 02 Aug 2010 30 Jun 2010 028-06377
13F-HR Open 13F-HR document View SEC filing for 13F-HR ASCII 29 Apr 2010 31 Mar 2010 028-06377
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A GENERAL FINANCE 08 Apr 2010
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A AMICAS 08 Mar 2010
SC 13G Open SC 13G document View SEC filing for SC 13G 16 Feb 2010
SC 13G Open SC 13G document View SEC filing for SC 13G DELIA 16 Feb 2010
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A PLX 16 Feb 2010
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A 12 Feb 2010
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A VIRTUAL RADIO 12 Feb 2010
SC 13G Open SC 13G document View SEC filing for SC 13G REGEN 12 Feb 2010
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A RTI 12 Feb 2010
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A XFONE 12 Feb 2010
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A CYTORI 12 Feb 2010
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A AMICAS 12 Feb 2010
SC 13G/A Open SC 13G/A document View SEC filing for SC 13G/A GEN FIN 12 Feb 2010
13F-HR Open 13F-HR document View SEC filing for 13F-HR GAGNON 04 Feb 2010 31 Dec 2009 028-06377

About this filer

GAGNON SECURITIES LLC files with the SEC under CIK 0001125725. This page aggregates EDGAR filings and related ownership activity.

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