Gagnon Securities, LLC logo

Gagnon Securities, LLC

Updated today

Client assets under management

$471,733,386

Clients

1,058

3% high-net-worth

Advisors

19

of 19 employees

Firm type

Team

5-30 advisors or >$500M in AUM

Clients per advisor

56

Typical

Average account size

$445,873

About

Gagnon Securities manages discretionary equity-focused accounts for individual and institutional clients and also provides brokerage services for retirement and non-retirement accounts. The firm is dually registered as an SEC investment adviser and a FINRA-member broker‑dealer and clears client accounts through National Financial Services.

The firm follows a research‑intensive, generalist, stock‑by‑stock approach aimed at aggressive capital appreciation, emphasizing company meetings, site visits, industry research and long-term conviction. Accounts are managed on a discretionary basis and the brochure stresses that the strategy can produce substantial volatility, so alignment between the firm’s approach and a client’s objectives is important.

The brochure highlights several features that distinguish Gagnon from many multi‑team peers: it routinely executes transactions through its broker‑dealer platform and charges transaction/commission‑based fees for many non‑retirement accounts rather than relying solely on asset‑based advisory fees, and it operates affiliated pooled vehicles and partner funds that reflect fund‑sponsor activity. The firm discloses a prior SEC enforcement order relating to reporting violations and describes clearing‑related credits and margin/short‑interest arrangements as potential conflicts; the brochure does not describe standalone financial planning services.

Client services

Portfolio management

Expertise

Active portfolio management

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Fee options

Commissions

Maximum of 2% of net trade amount per transaction plus transaction fee not to exceed $0.04 per share for non-retirement accounts

Other

Account minimum: $15,000

Main office location

Gagnon Securities, LLC

1370 6 Th Avenue, 26 Th Floor

New York NY 10019, United States

Number of offices

1

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

user avatar

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
user avatar

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
user avatar

Jessica V

Series 63, Series 65

New York, NY

Gagnon Securities, LLC

Jessica Vingiello is a financial advisor at Gagnon Securities, LLC in New York, NY, holding Series 63 and Series 65 designations with five years of industry experience. She has been with Gagnon Securities since 2020. 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 investment approach aimed at aggressive capital appreciation and operates affiliated pooled vehicles and partner funds.

Active portfolio management
user avatar

Adrienne G

Series 63

New York, NY

Gagnon Securities, LLC

Adrienne Garofalo is a financial advisor at Gagnon Securities, LLC with 17 years of industry experience. She holds a Series 63 designation and has been with Gagnon Securities since 2012. Outside of her advisory role, she volunteers as a Co-Chair for US Conference Events and Global Angels Chair with the nonprofit organization 100 Women in Finance. Gagnon Securities manages discretionary equity-focused accounts for both individual and institutional clients, employing a research-intensive, stock-by-stock approach aimed at aggressive capital appreciation. The firm operates as a dually registered SEC investment adviser and FINRA-member broker-dealer, offering brokerage services alongside its advisory business.

Active portfolio management
user avatar

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
user avatar

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
user avatar

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
user avatar

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, holding Series 63 and Series 65 licenses and possessing 11 years of industry experience. He has worked at Gagnon Securities since 2020, previously with Btig LLC and Ladenburg Thalmann & Co. 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, providing services through its broker-dealer platform and affiliated pooled vehicles.

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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