Mark Herndon

CIK: 0001754318

Transaction Breakdown

Open Market Buys (P)6 (100.0%)

High conviction signal

Open Market Sales (S)0 (0.0%)

Position reduction

Option Exercises (M)0 (0.0%)

Derivative conversions

Awards (A)0 (0.0%)

Compensation grants

Other (G, F, J, C, D, …)0 (0.0%)

Gifts, tax withholding, conversions, dispositions to the issuer and other codes

Companies & Roles (1)

HKHC

Horizon Kinetics Holding Corp

Officer

Discretionary Trading P&L

Holdings

Transaction History (6 total)

HKHC
Horizon Kinetics Holding Corp
Aug 20, 2026
Purchase(P)
Direct
200 shares at avg. $26.75$5K
HKHC
Horizon Kinetics Holding Corp
Aug 19, 2026
Purchase(P)
Direct
50 shares at avg. $26.50$1K
HKHC
Horizon Kinetics Holding Corp
May 20, 2026
Purchase(P)
Direct
100 shares at avg. $27.85$3K
HKHC
Horizon Kinetics Holding Corp
Mar 18, 2026
Purchase(P)
Direct
80 shares at avg. $33.03$3K
HKHC
Horizon Kinetics Holding Corp
Nov 20, 2025
Purchase(P)
Direct
100 shares at avg. $29.00$3K
HKHC
Horizon Kinetics Holding Corp
Jun 4, 2025
Purchase(P)
Direct
20 shares at avg. $40.18$803.6

		Type	Shares	Price		Ownership
Aug 20, 2026	HKHC Horizon Kinetics Holding Corp	Purchase(P)	200	$26.75	$5,350	Direct
Aug 19, 2026	HKHC Horizon Kinetics Holding Corp	Purchase(P)	50	$26.50	$1,325	Direct
May 20, 2026	HKHC Horizon Kinetics Holding Corp	Purchase(P)	100	$27.85	$2,785	Direct
Mar 18, 2026	HKHC Horizon Kinetics Holding Corp	Purchase(P)	80	$33.03	$2,642	Direct
Nov 20, 2025	HKHC Horizon Kinetics Holding Corp	Purchase(P)	100	$29.00	$2,900	Direct
Jun 4, 2025	HKHC Horizon Kinetics Holding Corp	Purchase(P)	20	$40.18	$804	Direct

1-6 of 6 transactions

About Herndon Mark

Herndon Mark (SEC CIK 0001754318) files insider reports with the SEC as Chief Financial Officer of Horizon Kinetics Holding Corp (HKHC).

Signal8 holds 5 ownership filings by Herndon Mark, all Form 4s, filed between Jun 5, 2025 and Aug 20, 2026. Those filings report 6 transactions, from Jun 4, 2025 to Aug 20, 2026. Signal8's Form 4 history starts in Sep 2024.

The business address on Herndon Mark's filings is in NEW YORK, NY.

Recent filings by Herndon Mark

Aug 20, 2026: Open-market purchase of HKHC shares (Form 4, code P).
Aug 19, 2026: Open-market purchase of HKHC shares (Form 4, code P).
May 20, 2026: Open-market purchase of HKHC shares (Form 4, code P).
Mar 18, 2026: Open-market purchase of HKHC shares (Form 4, code P).
Nov 20, 2025: Open-market purchase of HKHC shares (Form 4, code P).

Other insiders filing for Horizon Kinetics Holding Corp (HKHC)

Nagelberg Allison, Director
Brennan Alice C, Director
Roller Daniel J, Director
Rosenthal Brent D, Director
STAHL MURRAY, CEO and CIO
Maran Partners Fund, LP, Officer

How to read Form 4 transaction codes