Immuneering IMRX Insider Ownership

NASDAQ IMRX

$3.66 +0.07 (+1.95%)

At close: Oct 19, 2026 · 4:00 PM EDT

Insider Holdings by Owner

5.98Mn Shares

Insider Ownership Statistics

as of 30 Sep, 2026

Insider Ownership

5.59%

▼-1.78% pp QoQ

Shares Held by Insiders

3.62Mn

filed for Sep 2026

▼-24.11% QoQ

Shares Outstanding

64.70Mn

64,697,402 shares

Direct Holdings

3.09Mn

Indirect: 530.68K

Net Shares Traded (QoQ)

-1.15Mn

net selling in Sep 2026

Insiders Holding Shares

with Form 4 holdings on file

Shares Owned by Insiders

Shares held % of outstanding

Latest —

Average ownership —

Peak ownership —

Shares Purchased/Sold by Insiders

Bought Sold

Latest quarter —

Net over range —

Buying quarters —

Insider Ownership Summary

Updated Oct 10, 2026

Across the past 12 months, open-market trades by Immuneering insiders were all purchases, totaling $270,336 (60.25K shares).

Immuneering's open-market purchases in the past 12 months came from 6 insiders; no insider sold.
Among IMRX's insiders, Thomas J. Schall (Director) was the top open-market buyer in the past 12 months, with $101,041 of stock purchased (21.64K shares) and the latest purchase on January 15, 2026.
The newest open-market trade among Immuneering insiders came on June 23, 2026, when Benjamin J. Zeskind (President and CEO) made a purchase of 2.4K shares for $10,948.
Beyond open-market trades, insiders at Immuneering received 3.63K shares in stock awards in the last 12 months.
Per Business Quant data, Immuneering insiders hold 3.62Mn shares in total based on their latest Form 4 filings, down 24.11% from 4.77Mn shares at the end of Q2 2026.
Direct holdings account for 3.09Mn shares (85.33%) of IMRX's insider total, and indirect holdings through trusts, partnerships and family members for 530.68K shares (14.67%).
IMRX's insider total is spread across 11 insiders who have filed a Form 4 in the past two years.
IMRX's three largest insider shareholders, per their latest Form 4 filings, are Benjamin J. Zeskind (President and CEO, 2.32Mn shares), Peter Feinberg (Director, 684.45K shares) and Brett Matthew Hall (Chief Scientific Officer, 382.53K shares).
The largest insider, Benjamin J. Zeskind, holds 64.01% of IMRX's insider total.
Institutions owned 53.25% of IMRX shares as of Q2 2026; insiders' latest Form 4 filings account for about 5.59%, leaving roughly 41.16% with other investors, including the public.
A total of 23 Form 4 filings with transactions in Immuneering stock were made over the past 12 months, by 13 insiders.
These insider figures for Immuneering are based on Form 4 filings through July 17, 2026.

Form 4 Holdings

Insiders Holding IMRX

Insiders 14

Shares held 5.98Mn

Of outstanding 9.24%

#	Insider	Position	Direct	Indirect	Total	Share of Insiders	Last Filed
1	Asset Management, Lp Cormorant	TenPercentOwner	0	2,895,273	2,895,273	48.4%	03 Apr, 2024
2	Benjamin J. Zeskind	President And Ceo	2,315,252	0	2,315,252	38.7%	24 Jun, 2026
3	Brett Matthew Hall	Chief Scientific Officer	382,531	0	382,531	6.4%	16 Jun, 2026
4	Peter Feinberg	Director	0	135,441	135,441	2.3%	14 Jan, 2026
5	Thomas J. Schall	Director	74,530	0	74,530	1.2%	20 Jan, 2026
6	Ann E Berman	Director	67,465	0	67,465	1.1%	19 Mar, 2024
7	Leah R Neufeld	Chief People Officer	29,598	0	29,598	0.5%	17 Mar, 2026
8	Mallory Morales	Chief Accounting Officer	27,533	0	27,533	0.5%	02 Oct, 2025
9	Laurie Keating	Director	14,000	0	14,000	0.2%	17 May, 2022
10	Harold Eugene Brakewood	Chief Business Officer	11,050	0	11,050	0.2%	21 Jan, 2026
11	Biren Amin	Cfo, Treasurer	7,898	0	7,898	0.1%	12 May, 2022
12	Scott Barrett	Chief Medical Officer	7,563	0	7,563	0.1%	22 Mar, 2022
13	Diana Hausman	Director	2,500	3,000	5,500	0.1%	07 Jul, 2025
14	Michael Bookman	Chief Legal Officer, Secretary	4,870	0	4,870	0.1%	02 Oct, 2025

Each row is that insider’s most recently reported position, from Form 4 filings over the last 60 months — which is why this total does not tie to the quarterly series above, where a quarter counts only the insiders who filed in it. Shares held through a fund or institutional portfolio are counted on the institutional ownership page instead.

Form 4 Filings

224 Insider Transactions

Source SEC Form 4

Latest quarter Sep 2026

Date	Insider	Position	Transaction	Shares	Price	Value	Shares Held After	Ownership
16 Jul, 2026	Andrew Gengos	Chief Financial Officer	Acquired A	650,000	$0.00	$0	650,000	Direct
23 Jun, 2026	Benjamin J. Zeskind	President And Ceo	Acquired P	2,400	$4.56	$10.95K	2,315,252	Direct
15 Jun, 2026	Brett Matthew Hall	Chief Scientific Officer	Acquired P	6,035	$4.15	$25.05K	382,531	Direct
11 Jun, 2026	Thomas J. Schall	Director	Acquired A	33,350	$0.00	$0	33,350	Direct
11 Jun, 2026	Peter Feinberg	Director	Acquired A	33,350	$0.00	$0	33,350	Direct
11 Jun, 2026	Laurie Keating	Director	Acquired A	33,350	$0.00	$0	33,350	Direct
11 Jun, 2026	Robert J Carpenter	Director	Acquired A	33,350	$0.00	$0	33,350	Direct
11 Jun, 2026	Diana Hausman	Director	Acquired A	33,350	$0.00	$0	33,350	Direct
13 Mar, 2026	Leah R Neufeld	Chief People Officer	Acquired A	3,628	$4.29	$15.57K	29,598	Direct
03 Feb, 2026	Michael Bookman	Chief Legal Officer, Secretary	Acquired A	176,000	$0.00	$0	176,000	Direct
03 Feb, 2026	Benjamin J. Zeskind	President And Ceo	Acquired A	688,000	$0.00	$0	688,000	Direct
03 Feb, 2026	Mallory Morales	Svp Finance, Cao	Acquired A	140,000	$0.00	$0	140,000	Direct
03 Feb, 2026	Igor Matushansky	Chief Medical Officer	Acquired A	140,000	$0.00	$0	140,000	Direct
03 Feb, 2026	Brett Matthew Hall	Chief Scientific Officer	Acquired A	344,000	$0.00	$0	344,000	Direct
03 Feb, 2026	Harold Eugene Brakewood	Chief Business Officer	Acquired A	140,000	$0.00	$0	140,000	Direct
03 Feb, 2026	Leah R Neufeld	Chief People Officer	Acquired A	140,000	$0.00	$0	140,000	Direct
16 Jan, 2026	Harold Eugene Brakewood	Chief Business Officer	Acquired P	5,250	$4.76	$24.99K	11,050	Direct
15 Jan, 2026	Thomas J. Schall	Director	Acquired P	21,645	$4.67	$101.04K	74,530	Direct
15 Jan, 2026	Brett Matthew Hall	Chief Scientific Officer	Acquired P	2,298	$4.57	$10.50K	376,496	Direct
13 Jan, 2026	Leah R Neufeld	Chief People Officer	Acquired P	2,626	$4.15	$10.91K	25,970	Direct

Showing 1 to 20 of 224 transactions