Last Updated: September 2025 — New York, NY
Here’s what you need to know about New York, NY stockbroker Mack L. Miller:
- Name: Mack Leon Miller
- Alias: Mark Miller
- Current Employer: Spartan Capital Securities, LLC (Registered since 04/27/2017), 45 Broadway, 19th Floor, New York, NY 10006. Currently Suspended.
- Prior Firms: Dawson James Securities, Lampert Capital Markets, ViewTrade Securities, Arjent LLC, Woodstock Financial Group, Blackbook Capital, Coastal Equities, John Carris Investments, National Securities, Legend Merchant Group, International Assets Advisory, Buckman Buckman & Reid, First Merger Capital, Seaboard Securities, Ridgeway & Conger, Fordham Financial, Investors Capital Corp., Great Eastern Securities, Sky Capital, PHD Capital.
- CRD number: 2822317.
- Stockbroker / Financial Advisor. Yes
- Can Broker be Sued in FINRA: Yes
- Sanctioned by Securities Regulators: Yes
- Employment Separation after Allegations: Yes
- Highest Award or Settlement: $7,500
If you’ve sustained damages from Mr. Miller, discuss your case with experienced investment fraud lawyer Bob Rex at (877) 224-3199 for a free consultation.
Did You Lose Money With Mack L. Miller As Your Stockbroker?
FINRA Disciplinary Action (AWC) — Final (Docket No. 2018056490331): On August 2025, FINRA accepted an AWC in which Mr. Miller consented (without admitting or denying) to findings that he willfully violated Regulation Best Interest (SEC Rule 15l-1(a)(1)) by recommending to two senior customers a series of excessive and unsuitable trades that were not in the customers’ best interests. The activity generated $32,230 in commissions and the customers suffered $71,022 in realized losses. Sanction: Suspension in all capacities for nine months (9/02/2025–6/01/2026. Employing firm at time of activity: Spartan Capital Securities, LLC.
FINRA Disciplinary Action (AWC) — Final (Docket No. 2018057302701): April 2020, FINRA accepted an AWC finding quantitatively unsuitable trading in the account of a 79-year-old retired customer while Mr. Miller was associated with Dawson James Securities, LLC and Spartan Capital Securities, LLC. High turnover rate and cost-to-equity ratio. The customer incurred $69,633 in losses. Sanctions: Five-month suspension (5/04/2020–10/03/2020) and restitution plus interest.
Customer Disputes:
- 07/21/2014 (Coastal Equities): Written complaint alleging churning and unsuitability in May–June 2014; settled for $7,500 .
- 04/17/2017 / 05/18/2017 (Dawson James): Written complaints alleging misrepresentation and excessive trading (08/2016–04/2017; denied by the firm (no payment).
Allegations of Broker Misconduct Against Mack L. Miller
- Unsuitability / Quantitative Unsuitability:
- Excessive Trading
- Unauthorized Trading
- Failure to Act in the Customer’s Best Interest
- Misrepresentation
Other Cases Involving Unauthorized Trading
What is Excessive Trading (Churning)?
Churning According to U.S. Securities and Exchange Commission (SEC)
Other Investigations Involving Churning
Recover Your Investment Losses Now With Rex Securities Law
Other Investigations Involving Spartan Capital Securities Brokers
Our Investigations of Other Dawson James Brokers
If you have suffered investment losses in an account handled by Mack L. Miller, contact us for a complimentary consultation with an experienced securities lawyer to learn how you may be able to recover damages through FINRA arbitration.
With offices in Boca Raton, FL, and Austin, TX, stockbroker fraud attorney Bob Rex provides representation to investors nationwide who are seeking recovery of investment losses due to the negligence or fraud of stockbrokers, financial advisors, and broker-dealers.
If you have questions about how your account has been handled, call (877) 224-3199 to speak with an experienced securities attorney at no cost to you.
Most cases are handled on a contingent fee basis meaning that you do not pay legal fees unless we are successful.