Arcellx, Inc. (ACLX) Insider Ownership

Historic Insider Ownership Trends

As of April 17, 2026, the three largest insider holders of ACLX are Peter W. Sonsini (TenPercentOwner, 4.75Mn shares), Enterprise Associates 15, L.P. New (TenPercentOwner, 4.75Mn shares), Partners 15, L.P. Nea (TenPercentOwner, 4.75Mn shares).

Top Direct Holders

Insider ownership data is derived from the last 60 months of Form 4 SEC filings.
Holder Position Shares (Direct) Shares (Indirect) Report Date
Peter W. Sonsini - 0 4,746,083 22 Dec, 2022
Partners 15, L.P. Nea - 0 4,745,262 22 Dec, 2022
Enterprise Associates 15, L.P. New - 4,745,262 0 22 Dec, 2022
One Capital Management, Llc Sr - 0 4,487,174 15 May, 2023
Holdings A/S Novo - 4,016,878 0 09 Feb, 2022
Jill Carroll - 0 2,828,394 15 May, 2023
Lewis T Williams - 0 2,095,114 09 Feb, 2022
Jill Carroll - 0 2,033,196 09 Feb, 2022
One Capital Management, Llc Sr - 0 2,033,196 10 Feb, 2022
Jill Carroll - 0 1,479,148 25 Mar, 2024
Rami Elghandour - 174,887 0 04 Mar, 2026
Michelle Gilson Chief Financial Officer 28,938 0 19 Mar, 2026
Christopher Heery Chief Medical Officer 23,749 0 14 Jan, 2026

* Please note that the shares above only reflect shares from the fund portfolio and the institutional portfolio. Shares from the personal portfolio are excluded from this Institutional Ownership Page. See these insiders' latest transactions here on Insider Page.

Recent Insider Transactions

Detailed insider trading activity based on Form 4 SEC filings.
Download Data
Transaction Date Insider Name Security Class Transaction Type Shares Traded Price Shares Remaining Ownership Code
17 Mar, 2026 Michelle Gilson Common Stock D 5,000 $0.00 28,938 D G
04 Mar, 2026 Rami Elghandour Common Stock D 101,164 $0.00 174,887 D G
02 Jan, 2026 Rami Elghandour Common Stock A 55,459 $0.00 673,378 D M
03 Jan, 2026 Rami Elghandour Common Stock A 53,098 $0.00 726,476 D M
06 Jan, 2026 Rami Elghandour Common Stock A 55,991 $0.00 782,467 D M
27 Feb, 2026 Rami Elghandour Common Stock D 89,916 $113.92 276,051 D S
06 Jan, 2026 Michelle Gilson Common Stock A 20,530 $0.00 64,832 D M
25 Feb, 2026 Michelle Gilson Common Stock D 11,219 $113.82 33,938 D S
03 Jan, 2026 Michelle Gilson Common Stock A 15,340 $0.00 44,302 D M
19 Feb, 2026 Michelle Gilson Common Stock D 2,879 $67.73 50,662 D S
19 Feb, 2026 Michelle Gilson Common Stock D 5,405 $68.57 45,257 D S
19 Feb, 2026 Michelle Gilson Common Stock D 100 $69.38 45,157 D S
02 Jan, 2026 Michelle Gilson Common Stock A 20,496 $0.00 28,962 D M
17 Feb, 2026 Michelle Gilson Common Stock D 7,141 $69.21 57,691 D S
17 Feb, 2026 Michelle Gilson Common Stock D 4,150 $70.01 53,541 D S
11 Feb, 2026 Rami Elghandour Common Stock D 218,500 $0.00 563,967 D G
11 Feb, 2026 Rami Elghandour Common Stock D 198,000 $0.00 365,967 D G
20 Jan, 2026 David Charles Lubner Common Stock A 6,000 $6.28 27,659 D M
20 Jan, 2026 David Charles Lubner Common Stock D 6,000 $75.00 21,659 D S
20 Jan, 2026 David Charles Lubner Stock Option (right to buy) D 6,000 $0.00 59,405 D M