Rachel E. Haurwitz - 20 Feb 2026 Form 4 Insider Report for Caribou Biosciences, Inc. (CRBU)

Role
President and CEO, Director
Signature
/s/ Barbara G. McClung, as attorney-in-fact
Issuer symbol
CRBU
Transactions as of
20 Feb 2026
Net transactions value
$0
Form type
4
Filing time
20 Feb 2026, 17:26:26 UTC
Previous filing
17 Mar 2025
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Haurwitz Rachel E. President and CEO, Director C/O CARIBOU BIOSCIENCES, INC., 2929 7TH STREET, SUITE 105, BERKELEY /s/ Barbara G. McClung, as attorney-in-fact 20 Feb 2026 0001670579

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction CRBU Common Stock Award $0 +151,700 +51% $0.000000 447,150 20 Feb 2026 Direct F1
holding CRBU Common Stock 3,369,395 20 Feb 2026 By Trust F2

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 CRBU Option to purchase Common Stock Award $0 +682,500 $0.000000 682,500 20 Feb 2026 Common Stock 682,500 $1.80 Direct F3
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 This reflects restricted stock units ("RSUs") that vest in four equal annual installments beginning on February 20, 2027, subject to the reporting person continuing to provide service to the Issuer through the applicable vesting dates. The RSUs will be settled in stock within 30 days after each vesting date.
F2 Shares are held by The City Canyon Family Trust dated May 31, 2021, of which the Reporting Person is a Co-Trustee with her spouse.
F3 1/48 of the total number of shares subject to this option will vest on each monthly anniversary of the grant date such that the option will be fully vested on February 20, 2030, subject to the reporting person continuing to provide service to the Issuer through each such vesting date.

Remarks:

The reporting person has elected, consistent with the terms of a durable sell-to-cover instruction, to pay cash to satisfy withholding tax obligations due in connection with the February 20, 2026 vesting of previously-granted RSUs.