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WH

William C. Horn

CITIZENS JMP SECURITIES
BOSTON, MA 02110
Some features on this profile are disabled
CRD#: 2234778
WH

Professional summary

William Canniff Horn III, who also goes by Bill Canniff, William Canniff Horn III, is a registered financial professional currently at CITIZENS JMP SECURITIES, LLC located in Boston, Massachusetts.

William is registered as a RR (Registered Representative) and started their career in finance in 1992. William has worked at 7 firms and has passed the Series 63, Series 82TO, Series 22TO, Series 99TO, Series 7TO, SIE, Series 79, Series 7 and Series 24 exams.

Question & Answer

Are you a "fiduciary"?
No

Aliases

Bill Canniff | William Canniff Horn Iii

Other business activities

Outside business activity is any business or activity undertaken by an advisor that is outside the scope of their relationship with their firm (e.g., consulting services, real estate, freelance work, teaching, etc.). Investors should stay informed about these activities to ensure no conflicts of interest.
The advisor shows no other business activity.

Blog Corner

CRS (Client Relationship Summary) - BD

Click below to view William Canniff Horn III's CRS (Customer Relationship Summary).
CRS (Customer Relationship Summary)

Certified licenses

Advisors may have various certifications and credentials from different organizations. AdvisorCheck highlights these seven certifications - AIF®, CFP®, ChFC®, CFA, CLU®, CIMA®, CPWA®
None

Experience

Current

December 9, 2025 - Present

CITIZENS JMP SECURITIES, LLC

Office #1: 28 State Street 15th Floor, Boston, MA 02110
BD
CRD#: 22208
BOSTON, MA
Past

April 12, 2024 - July 14, 2025

M&T SECURITIES, INC.

BD
CRD#: 17358
BALTIMORE, MD
Past

August 1, 2023 - March 28, 2024

CITIZENS JMP SECURITIES, LLC

BD
CRD#: 22208
BOSTON, MA
Past

May 24, 2018 - August 1, 2023

CITIZENS CAPITAL MARKETS

BD
CRD#: 277073
BOSTON, MA
Past

August 28, 2002 - April 13, 2004

STATE STREET GLOBAL ADVISORS FUNDS DISTRIBUTORS, LLC

BD
CRD#: 30107
BOSTON, MA
Past

October 4, 2000 - April 2, 2001

ONECORE SECURITIES, INC.

BD
CRD#: 45813
BEDFORD, MA
Past

March 22, 1999 - July 14, 2000

FIDELITY BROKERAGE SERVICES LLC

BD
CRD#: 7784
SMITHFIELD, RI
Past

July 20, 1992 - March 22, 1999

NATIONAL FINANCIAL SERVICES LLC

BD
CRD#: 13041
BOSTON, MA

State Registrations and Notice Filings

Listed states reflect where the advisor is authorized to serve clients under state regulations.

Visual representation of state registrations

This advisor is not registered in any state.

Exams

State Security Law Exam
RR
Series 63
Date: 6/26/1992
Uniform Securities Agent State Law Examination
General Industry/Product Exam
RR
Series 82TO
Date: 4/12/2024
Limited Representative-Private Securities Offerings
General Industry/Product Exam
RR
Series 22TO
Date: 1/2/2023
Direct Participation Programs Representative Examination
General Industry/Product Exam
RR
Series 99TO
Date: 1/2/2023
Operations Professional Examination
General Industry/Product Exam
RR
Series 7TO
Date: 6/22/2020
General Securities Representative Examination
General Industry/Product Exam
RR
SIE
Date: 10/1/2018
Securities Industry Essentials Examination
General Industry/Product Exam
RR
Series 79
Date: 5/24/2018
Investment Banking Registered Representative Examination
General Industry/Product Exam
RR
Series 7
Date: 7/16/1992
General Securities Representative Examination
Principal/Supervisory Exam
RR
Series 24
Date: 3/28/2019
General Securities Principal Examination
SRO Registrations
RR
FINRA
SRO Registrations
RR
Nasdaq Stock Market

Current Firm

CJ
CITIZENS JMP SECURITIES, LLC
CITIZENS | TRINITY CAPITAL | MITCHUM, JONES & TEMPLETON, INC. | JOLSON MERCHANT PARTNERS | JMP SECURITIES LLC | JMP SECURITIES | DH CAPITAL | CITIZENS M&A ADVISORY | CITIZENS JMP SECURITIES, LLC | CITIZENS JMP | CITIZENS CAPITAL MARKETS & ADVISORY | CITIZENS CAPITAL MARKETS

CRD#: 22208 / SEC#: , 8-39613

BD
Broker-Dealer Firm Regulated by FINRA (San Francisco district office)
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Contact information

Main Address
101 California Street Ste 1700, San Francisco, CA 94111
Mailing Address
101 California Street Ste 1700, San Francisco, CA 94111
Phone number
(415) 835-8900
Established
Delaware since 01/01/2002
Firm type
Limited Liability Company
Fiscal year end
December
Firm Size
Medium
# of Employees

FINRA licenses (51 States and Territories)

Blank US states mapAlaskaHawaiiAlabamaArkansasArizonaCaliforniaColoradoConnecticutDelawareFloridaGeorgiaIowaIdahoIllinoisIndianaKansasKentuckyLouisianaMassachusettsMarylandMaineMichiganMinnesotaMissouriMississippiMontanaNorth CarolinaNorth DakotaNebraskaNew HampshireNew JerseyNew MexicoNevadaNew YorkOhioOklahomaOregonPennsylvaniaRhode IslandSouth CarolinaSouth DakotaTennesseeTexasUtahVirginiaVermontWisconsinWest VirginiaWyoming

Documents

Customer Relationship Summary (CRS / FINRA)

Direct owners and executive officers

NamePositionCRD#
JMP HOLDING LLCPARENT COMPANY
CONROY, WALTER IVORGENERAL COUNSEL6641487
GREGORY, JOHNPRESIDENT4600619
JACKSON, RAYMOND SIVACHIEF FINANCIAL OFFICER5563363
MCLAUGHLIN, BRENDANCHIEF COMPLIANCE OFFICER2562815
O'DAY, JAMES CORTLANDHEAD OF EQUITIES5618215
PITARRESI, JOHN CHARLESSENIOR REGISTERED OPTIONS PRINCIPAL (SROP)2064758
SLADER, GAVIN WILLEYHEAD OF INVESTMENT BANKING4130019
SPURR, JEFFREY HOLMESHEAD OF RESEARCH1384716
SUCHY, GREGORY JOHNCHIEF OPERATING OFFICER / PRINCIPAL OPERATIONS OFFICER5907019
WHITEHEAD, AIDAN PETERHEAD OF TRADING & SALES TRADING2474257
XIAO, ZHUO VIVIAN XUANFINOP5121578

Disclosures

Regulatory Event6

Red Flags

Disclosures can be potential red flags, including customer disputes, regulatory fines, employer terminations, bankruptcies, judgments, liens, or certain criminal activities.

Check for any disclosures as part of your thorough research when choosing an advisor.

Company Information

CITIZENS JMP SECURITIES, LLC

CRD#: 22208Boston, MA 02110

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