Maxcyte MXCT Insider Ownership

NASDAQ MXCT

$1.30 +0.00 (+0.00%)

At close: Oct 19, 2026 · 4:00 PM EDT

Insider Holdings by Owner

13.11Mn Shares

Insider Ownership Statistics

as of 30 Sep, 2026

Insider Ownership

2.20%

▼-0.023% pp QoQ

Shares Held by Insiders

2.35Mn

filed for Sep 2026

▼-1.05% QoQ

Shares Outstanding

106.82Mn

106,822,633 shares

Direct Holdings

2.35Mn

Indirect: 0

Net Shares Traded (QoQ)

-25.00K

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

Over the past 12 months, Maxcyte insiders sold $8,266 of stock on the open market (10.14K shares) and made no open-market purchases.

Douglas J. Swirsky (Chief Financial Officer) was the top open-market seller of Maxcyte over the past 12 months, with $8,266 sold (10.14K shares) and the latest sale on March 17, 2026.
In transactions other than open-market trades, Maxcyte insiders received 517.92K shares in stock awards over the past 12 months.
According to Business Quant data, insiders at Maxcyte reported 2.35Mn shares in total in their latest Form 4 filings, down 1.05% from 2.38Mn shares at the end of Q2 2026 and down 1.40% from 2.39Mn shares at the end of Q3 2025.
All of the 2.35Mn shares held by Maxcyte insiders are held directly, none through trusts, partnerships or other entities.
MXCT's insider total is spread across 13 insiders who have filed a Form 4 in the past two years.
MXCT's three largest insider shareholders, per their latest Form 4 filings, are Maher Masoud (President and CEO, 475K shares), Stanley C. Erck (Director, 428.75K shares) and Richard Douglas (Director, 261K shares).
Maher Masoud holds 20.18% of the combined insider position in Maxcyte.
Institutional holders reported 59.10% of Maxcyte's outstanding shares for Q2 2026; insiders' latest Form 4 filings put their stake at about 2.20%, and other investors, including the public, hold the remaining 38.70%.
In the last 12 months, 12 Form 4 filings with transactions in MXCT stock came from 11 insiders.
The insider holdings and trades above for Maxcyte reflect Form 4 filings through June 22, 2026.

Form 4 Holdings

Insiders Holding MXCT

Insiders 17

Shares held 13.11Mn

Of outstanding 12.27%

#	Insider	Position	Direct	Total	Share of Insiders	Last Filed
1	Partners Master Fund, L.P. Casdin	TenPercentOwner	10,000,000	10,000,000	76.3%	05 Oct, 2022
2	Maher Masoud	President And Ceo	475,000	475,000	3.6%	31 Mar, 2026
3	Stanley C Erck	Director	428,749	428,749	3.3%	22 Jun, 2026
4	Art Mandell	Director	395,851	395,851	3.0%	13 Jun, 2024
5	Douglas Doerfler	President And Ceo	333,197	333,197	2.5%	06 Dec, 2023
6	Richard Douglas	Director	260,998	260,998	2.0%	22 Jun, 2026
7	John Joseph Johnston	Director	201,581	201,581	1.5%	22 Jun, 2026
8	Parmeet Ahuja	Chief Financial Officer	187,500	187,500	1.4%	17 Apr, 2026
9	William W Brooke	Director	181,300	181,300	1.4%	22 Jun, 2026
10	Douglas J Swirsky	Chief Financial Officer	151,669	151,669	1.2%	19 Mar, 2026
11	Cynthia Collins	Director	111,310	111,310	0.8%	22 Jun, 2026
12	Yasir B. Al-Wakeel	Director	80,998	80,998	0.6%	22 Jun, 2026
13	Patrick J Balthrop	Director	80,998	80,998	0.6%	22 Jun, 2026
14	Rekha Hemrajani	Director	70,314	70,314	0.5%	22 Jun, 2026
15	David I. Sandoval	General Counsel	64,219	64,219	0.5%	20 Mar, 2025
16	Ali Soleymannezhad	Chief Commercial Officer	59,439	59,439	0.5%	20 Mar, 2025
17	Thomas M. Ross	Evp, Global Sales	25,000	25,000	0.2%	05 Aug, 2024

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

409 Insider Transactions

Source SEC Form 4

Latest quarter Sep 2026

Date	Insider	Position	Transaction	Shares	Price	Value	Shares Held After	Ownership
17 Jun, 2026	Rekha Hemrajani	Director	Acquired A	30,421	$0.00	$0	70,314	Direct
17 Jun, 2026	Patrick J Balthrop	Director	Acquired A	30,421	$0.00	$0	80,998	Direct
17 Jun, 2026	Richard Douglas	Director	Acquired A	30,421	$0.00	$0	260,998	Direct
17 Jun, 2026	John Joseph Johnston	Director	Acquired A	30,421	$0.00	$0	201,581	Direct
17 Jun, 2026	Stanley C Erck	Director	Acquired A	30,421	$0.00	$0	428,749	Direct
17 Jun, 2026	William W Brooke	Director	Acquired A	30,421	$0.00	$0	181,300	Direct
17 Jun, 2026	Yasir B. Al-Wakeel	Director	Acquired A	30,421	$0.00	$0	80,998	Direct
17 Jun, 2026	Cynthia Collins	Director	Acquired A	30,421	$0.00	$0	111,310	Direct
17 Jun, 2026	Patrick J Balthrop	Director	Acquired A	49,579	$0.00	$0	49,579	Direct
17 Jun, 2026	William W Brooke	Director	Acquired A	49,579	$0.00	$0	49,579	Direct
17 Jun, 2026	Richard Douglas	Director	Acquired A	49,579	$0.00	$0	49,579	Direct
17 Jun, 2026	Cynthia Collins	Director	Acquired A	49,579	$0.00	$0	49,579	Direct
17 Jun, 2026	Rekha Hemrajani	Director	Acquired A	49,579	$0.00	$0	49,579	Direct
17 Jun, 2026	John Joseph Johnston	Director	Acquired A	49,579	$0.00	$0	49,579	Direct
17 Jun, 2026	Yasir B. Al-Wakeel	Director	Acquired A	49,579	$0.00	$0	49,579	Direct
17 Jun, 2026	Stanley C Erck	Director	Acquired A	49,579	$0.00	$0	49,579	Direct
15 Apr, 2026	Parmeet Ahuja	Chief Financial Officer	Acquired A	187,500	$0.00	$0	187,500	Direct
30 Mar, 2026	Parmeet Ahuja	Chief Financial Officer	Acquired A	375,000	$0.00	$0	375,000	Direct
27 Mar, 2026	Maher Masoud	President And Ceo	Acquired A	300,000	$0.00	$0	475,000	Direct
27 Mar, 2026	Maher Masoud	President And Ceo	Acquired A	600,000	$0.00	$0	600,000	Direct

Showing 1 to 20 of 409 transactions