Michelle Gilson - 02 Jan 2026 Form 4 Insider Report for Arcellx, Inc. (ACLX)

Role
CHIEF FINANCIAL OFFICER
Signature
/s/ Michelle Gilson
Issuer symbol
ACLX
Transactions as of
02 Jan 2026
Net transactions value
$0
Form type
4
Filing time
06 Jan 2026, 20:14:35 UTC
Previous filing
15 Oct 2025
Next filing
18 Feb 2026
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Gilson Michelle CHIEF FINANCIAL OFFICER C/O ARCELLX, INC., 800 BRIDGE PARKWAY, REDWOOD CITY /s/ Michelle Gilson 06 Jan 2026 0001930862

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction ACLX Common Stock Options Exercise $0 +20,496 +242% $0.000000 28,962 02 Jan 2026 Direct
transaction ACLX Common Stock Options Exercise $0 +15,340 +53% $0.000000 44,302 03 Jan 2026 Direct
transaction ACLX Common Stock Options Exercise $0 +20,530 +46% $0.000000 64,832 06 Jan 2026 Direct

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Underlying Class Amount Exercise Price Ownership Footnotes
transaction ACLX Restricted Stock Unit Award $0 +88,542 $0.000000 88,542 02 Jan 2026 Common Stock 88,542 Direct F1, F2
transaction ACLX Restricted Stock Unit Options Exercise $0 -20,496 -50% $0.000000 20,496 02 Jan 2026 Common Stock 20,496 Direct F1, F3
transaction ACLX Restricted Stock Unit Options Exercise $0 -15,340 -100% $0.000000 0 03 Jan 2026 Common Stock 15,340 Direct F1, F4
transaction ACLX Restricted Stock Unit Options Exercise $0 -20,530 -25% $0.000000 61,590 06 Jan 2026 Common Stock 20,530 Direct F1, F5
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 Each restricted stock unit ("RSU") represents a contingent right to receive one share of the Issuer's Common Stock.
F2 Subject to the Reporting Person continuing to be a Service Provider (as defined in the Issuer's 2022 Equity Incentive Plan) through each applicable vesting date, one-fourth (1/4th) of the RSUs subject to the award will vest each year following the RSU Grant Date on the same day of the month as the RSU Grant Date (or, if there is no corresponding day in a particular month, then the last day of the month) over four (4) years. "RSU Grant Date" shall mean January 2, 2026.
F3 Subject to the Reporting Person continuing to be a Service Provider (as defined in the Issuer's 2022 Equity Incentive Plan) through each applicable vesting date, one-third (1/3rd) of the RSUs subject to the award will vest each year following the RSU Grant Date on the same day of the month as the RSU Grant Date (or, if there is no corresponding day in a particular month, then the last day of the month) over three (3) years. "RSU Grant Date" shall mean January 2, 2024.
F4 Subject to the Reporting Person continuing to be a Service Provider (as defined in the Issuer's 2022 Equity Incentive Plan) through each applicable vesting date, one-third (1/3rd) of the RSUs subject to the award will vest each year following the RSU Grant Date on the same day of the month as the RSU Grant Date (or, if there is no corresponding day in a particular month, then the last day of the month) over three (3) years. "RSU Grant Date" shall mean January 3, 2023.
F5 Subject to the Reporting Person continuing to be a Service Provider (as defined in the Issuer's 2022 Equity Incentive Plan) through each applicable vesting date, one-fourth (1/4th) of the RSUs subject to the award will vest each year following the RSU Grant Date on the same day of the month as the RSU Grant Date (or, if there is no corresponding day in a particular month, then the last day of the month) over four (4) years. "RSU Grant Date" shall mean January 6, 2025.