Gagnon Securities, LLC logo

Gagnon Securities, LLC

Updated today

Client AUM

$471,733,386

Clients

1,058

Advisors

19

of 19 employees

About

Gagnon Securities serves individual and institutional clients through discretionary portfolio management, retirement accounts, trusts and custodial arrangements, overseeing approximately $529.7 million in regulatory assets under management across a team of advisors and about 1,058 client relationships. The firm is dually registered as an SEC-registered investment adviser and a FINRA-member broker‑dealer and provides both advisory and brokerage services with clearing through National Financial Services (NFS).

The firm follows a research-intensive, generalist equity approach focused on stock-by-stock selection for capital appreciation with a long-term orientation, and it manages accounts on a discretionary basis under limited trading authorizations. Its platform permits more active strategies—including the use of margin and short positions in margin accounts and separately managed hedged accounts—so portfolio construction can include hedging and leveraging techniques alongside long-only exposures.

Gagnon Securities is notable among similarly sized team firms for operating as both adviser and broker‑dealer with transaction-based commissions and per‑share fees on non‑retirement accounts, maintaining affiliated investment vehicles and manager relationships (including domestic long/short funds and fund‑of‑funds structures), and participating in programs such as fully paid securities lending through its custodian. The firm discloses a prior SEC enforcement matter involving reporting violations, and its brochure emphasizes portfolio management as the primary service rather than comprehensive financial planning.

Client services

Portfolio management

Expertise

Active portfolio management

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Fee options

Commissions

Maximum commission rate of 2% of the net trade amount per buy and sell transaction; up to $0.04 cents per share transaction fee

Other

Account minimum: $15,000

Main office

1370 Avenue of the Americas

New York NY 10019

Advisors at this office

19

Most active in

Alabama · Arizona · Arkansas · California · Colorado · Connecticut · District of Columbia · Florida · Georgia · Idaho · Illinois · Indiana · Iowa · Kansas · Kentucky · Louisiana · Maine · Maryland · Massachusetts · Michigan · Minnesota · Mississippi · Missouri · Montana · Nebraska · Nevada · New Hampshire · New Jersey · New Mexico · New York · North Carolina · North Dakota · Ohio · Oklahoma · Oregon · Pennsylvania · Rhode Island · South Carolina · South Dakota · Tennessee · Texas · Utah · Vermont · Virgin Islands · Virginia · Washington · Wisconsin · Wyoming

Disclosures

Exclamation point means they have disclosures of this type. Check mark means no disclosures of this type were found.

Business activities & affiliations

Advisors at this firm

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Neil G

Series 63, Series 65

New York, NY

Gagnon Securities, LLC

Neil Gagnon is a financial advisor at Gagnon Securities, LLC with 55 years of industry experience. He holds Series 63 and Series 65 licenses and has been with Gagnon Securities since 1999. Outside of his advisory role, he is the owner of an ice cream shop and serves as a trustee of the Gagnon Family Foundation, which makes charitable contributions to various organizations. Gagnon Securities manages discretionary equity-focused accounts for individual and institutional clients, using a research-intensive, stock-by-stock approach aimed at aggressive capital appreciation. The firm operates as both an SEC-registered investment adviser and a FINRA-member broker-dealer, offering brokerage services and affiliated pooled vehicles.

Active portfolio management
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Jonathan R

Series 63

New York, NY

Gagnon Securities, LLC

Jonathan Robohm is a financial advisor with Gagnon Securities, LLC, holding a Series 63 designation and 25 years of industry experience. He has been with Gagnon Securities since 2001. Robohm is a partner at Gagnon Administrative Services and co-manages the GIS Fund of Funds. Gagnon Securities manages discretionary, equity-focused accounts for individual and institutional clients using a research-intensive, stock-by-stock approach aimed at aggressive capital appreciation. The firm operates as both an SEC-registered investment adviser and a FINRA-member broker-dealer and offers brokerage services for retirement and non-retirement accounts.

Active portfolio management
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Jessica V

Series 63, Series 65

New York, NY

Gagnon Securities, LLC

Jessica Vingiello is a financial advisor at Gagnon Securities, LLC with six years of industry experience. She holds Series 63 and Series 65 designations and has been with Gagnon Securities since 2020. Gagnon Securities serves individual and institutional clients through discretionary portfolio management, retirement accounts, trusts, and custodial arrangements. The firm employs a research-intensive, generalist equity approach focused on stock-by-stock selection for capital appreciation with a long-term orientation.

Active portfolio management
user avatar

Adrienne G

Series 63

New York, NY

Gagnon Securities, LLC

Adrienne Garofalo is a financial advisor with Gagnon Securities, LLC, holding a Series 63 designation and 18 years of industry experience. She has been with Gagnon Securities since 2012. Garofalo volunteers as a Co-Chair for US Conference Events and Global Angels Chair for the nonprofit organization 100 Women in Finance and also provides administrative support to the Gagnon Family Foundation. Gagnon Securities serves individual and institutional clients through discretionary portfolio management, retirement accounts, trusts, and custodial arrangements, overseeing over $529 million in regulatory assets. The firm employs a research-intensive, generalist equity approach focused on long-term capital appreciation and offers both advisory and brokerage services.

Active portfolio management
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Maureen D

Series 63

New York, NY

Gagnon Securities, LLC

Maureen Drew is a financial advisor at Gagnon Securities, LLC with 30 years of industry experience. She has been with Gagnon Securities since 1999 and holds a Series 63 designation. Gagnon Securities manages discretionary equity-focused accounts for individual and institutional clients, employing a research-intensive, stock-by-stock approach aimed at aggressive capital appreciation. The firm is dually registered as an SEC investment adviser and FINRA-member broker-dealer, offering brokerage services and operating affiliated pooled vehicles and partner funds.

Active portfolio management
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Lisa F

Series 63

New York, NY

Gagnon Securities, LLC

Lisa Ferrante is a financial advisor with Gagnon Securities, LLC in New York, NY, holding a Series 63 designation and 27 years of industry experience. She has been with Gagnon Securities since 2001. Additionally, she provides compliance support through Gagnon Administrative Services and serves as a partner in related investment entities. Gagnon Securities manages discretionary, equity-focused accounts for individual and institutional clients, employing a research-intensive, stock-by-stock approach aimed at aggressive capital appreciation. The firm operates both as an SEC-registered investment adviser and a FINRA-member broker-dealer.

Active portfolio management
user avatar

Willis T

Series 63

New York, NY

Gagnon Securities, LLC

Willis Taylor is a financial advisor with Gagnon Securities, LLC in New York, NY, holding a Series 63 designation and 25 years of industry experience. He has been with Gagnon Securities since 2005. Outside of his advisory role, Taylor is the managing member of Old Growth Partners, a long/short equity hedge fund, and co-managing member of Darwin Partners LP, another long/short equity hedge fund. Gagnon Securities manages discretionary equity-focused accounts for individual and institutional clients and provides brokerage services for retirement and non-retirement accounts. The firm employs a research-intensive, stock-by-stock approach aimed at aggressive capital appreciation, combining company meetings, site visits, and industry research.

Active portfolio management
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Matthew J

Series 63

New York, NY

Gagnon Securities, LLC

Matthew Jampole is a financial advisor at Gagnon Securities, LLC with 26 years of industry experience. He holds a Series 63 designation and has been with Gagnon Securities and Herzog, Heine, Geduld, Inc. since 2000. Gagnon Securities manages discretionary equity-focused accounts for individual and institutional clients and provides brokerage services for retirement and non-retirement accounts. The firm employs a research-intensive, stock-by-stock approach aimed at aggressive capital appreciation and operates both advisory and broker-dealer platforms, including affiliated pooled vehicles and partner funds.

Active portfolio management
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James C

Series 63, Series 65

New York, NY

Gagnon Securities, LLC

James Colby is a financial advisor with Gagnon Securities, LLC in New York, NY, holding Series 63 and Series 65 registrations and 12 years of industry experience. His prior experience includes roles at Btig LLC and Ladenburg Thalmann & Co. Gagnon Securities serves individual and institutional clients through discretionary portfolio management, retirement accounts, trusts, and custodial arrangements. The firm employs a research-intensive, generalist equity approach focused on stock-by-stock selection for capital appreciation with a long-term orientation.

Active portfolio management
user avatar

Marianne D

Series 63

New York, NY

Gagnon Securities, LLC

Marianne D’alessandro is a financial advisor with Gagnon Securities, LLC, holding a Series 63 designation and 19 years of industry experience. She has been with Gagnon Securities since 2005. Outside of her advisory role, she provides administrative support for a family-owned real estate business. Gagnon Securities manages discretionary equity-focused accounts for individual and institutional clients, utilizing a research-intensive, stock-by-stock approach aimed at aggressive capital appreciation. The firm is dually registered as an SEC investment adviser and FINRA-member broker-dealer, offering both advisory and brokerage services.

Active portfolio management
user avatar

Henry B

Series 63

New York, NY

Gagnon Securities, LLC

Henry Beinstein is a financial advisor at Gagnon Securities, LLC with 23 years of industry experience. He holds a Series 63 designation and has been with Gagnon Securities since 2002. Beinstein is a Certified Public Accountant and Chartered Global Management Accountant, serving as an Independent Director and Chairman of the Audit Committee at Vector Group LTD, as well as holding independent board roles at the Lombardy Hotel and the Omega Institute, a nonprofit organization. Gagnon Securities manages discretionary equity-focused accounts for individual and institutional clients, using a research-intensive, stock-by-stock approach aimed at aggressive capital appreciation. The firm operates both as an SEC investment adviser and a FINRA-member broker-dealer, offering brokerage services and managing affiliated pooled vehicles and partner funds.

Active portfolio management
user avatar

Brian G

Series 63

New York, NY

Gagnon Securities, LLC

Brian Gagnon is a financial advisor at Gagnon Securities, LLC with 34 years of industry experience. He holds a Series 63 designation and has been with Gagnon Securities since 1999. Outside of his advisory role, he serves as President of Hilltop Aviation Services, LLC and acts as a trustee for the Gagnon Family Foundation. He is also an advisory council member of the National Kidney Foundation Innovation Fund. Gagnon Securities manages discretionary equity-focused accounts for individual and institutional clients and provides brokerage services for retirement and non-retirement accounts. The firm employs a research-intensive, stock-by-stock approach aimed at aggressive capital appreciation and operates affiliated pooled vehicles alongside its broker-dealer platform.

Active portfolio management
user avatar

Gabrielle R

Series 63

New York, NY

Gagnon Securities, LLC

Gabrielle Rosenfeld is a financial advisor at Gagnon Securities, LLC with six years of industry experience. She holds a Series 63 designation and has worked at Gagnon Securities since 2019, following a year at Third Bridge and three years at Bucknell University. Gagnon Securities manages discretionary equity-focused accounts for individual and institutional clients, offering both investment advisory and brokerage services. The firm employs a research-intensive, generalist, stock-by-stock approach aimed at aggressive capital appreciation and operates affiliated pooled vehicles and partner funds alongside its broker-dealer platform.

Active portfolio management
user avatar

Sarah J

Series 63

New York, NY

Gagnon Securities, LLC

Sarah Jilla is a financial advisor at Gagnon Securities, LLC in New York, NY, with 11 years of industry experience. She holds a Series 63 designation and has been with Gagnon Securities since 2011. Outside of her advisory role, she owns an Etsy shop selling artwork as stickers and works as a social media consultant. Gagnon Securities manages discretionary equity-focused accounts for individual and institutional clients, employing a research-intensive, stock-by-stock approach aimed at aggressive capital appreciation. The firm operates as both an SEC-registered investment adviser and a FINRA-member broker-dealer, offering brokerage services and managing affiliated pooled investment vehicles.

Active portfolio management
user avatar

Dwight L

Series 63

New York, NY

Gagnon Securities, LLC

Dwight Lee is a financial advisor at Gagnon Securities, LLC in New York, NY, holding a Series 63 designation with 19 years of industry experience. He has been associated with Upland Associates since 2000 and serves as managing member for multiple investment vehicles including Upland Asset Management and GagnonLee Associates. Lee holds several nonprofit board roles, including chairman of the investment committee at The Century Association and trustee and vice chair of the board at The Graduate Center Foundation, Inc. Gagnon Securities manages discretionary equity-focused accounts for individual and institutional clients, employing a research-intensive, stock-by-stock approach aimed at aggressive capital appreciation. The firm provides brokerage services and operates affiliated pooled vehicles alongside its advisory business.

Active portfolio management
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