Caribou Biosciences (CRBU) CFO awarded 247,500 options and 55,000 RSUs

Rhea-AI Filing Summary

Caribou Biosciences, Inc. Chief Financial Officer Sriram Ryali reported equity awards consisting of stock options and restricted stock units. He was granted an option to purchase 247,500 shares of common stock at an exercise price of $0.00 per share.

The option vests over time, with 1/48 of the shares vesting monthly so that it is fully vested by February 20, 2030, contingent on continued service. He also received 55,000 shares of common stock in the form of RSUs that vest in four equal annual installments beginning on February 20, 2027, also subject to continued service, and will be settled in stock within 30 days after each vesting date.

Insider Trade Summary

2 transactions reported

Mixed 2 txns

Insider Ryali Sriram

Role Chief Financial Officer

Type	Security	Shares	Price	Value
Grant/Award	Option to purchase Common Stock	247,500	$0.00	--
Grant/Award	Common Stock	55,000	$0.00	--

Holdings After Transaction: Option to purchase Common Stock — 247,500 shares (Direct); Common Stock — 72,360 shares (Direct)

Footnotes (1)

1. 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. 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.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Ryali Sriram

(Last) (First) (Middle)

C/O CARIBOU BIOSCIENCES, INC.

2929 7TH STREET, SUITE 105

(Street)

BERKELEY CA 94710

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Caribou Biosciences, Inc. [ CRBU ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Financial Officer

3. Date of Earliest Transaction (Month/Day/Year)
02/20/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	02/20/2026		A		55,000(1)	A	$0	72,360	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Option to purchase Common Stock	$1.8	02/20/2026		A		247,500		(2)	02/19/2036	Common Stock	247,500	$0	247,500	D

Explanation of Responses:

1. 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.

2. 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:

	/s/ Barbara G. McClung, as attorney-in-fact	02/20/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What insider transactions did Caribou Biosciences (CRBU) report for Sriram Ryali?

Caribou Biosciences reported equity awards to CFO Sriram Ryali, including stock options and restricted stock units. These awards are time-based and vest over several years, aligning his compensation with long-term company performance and continued service requirements.

How many stock options did Caribou Biosciences’ CFO receive in this Form 4?

The CFO received an option to purchase 247,500 shares of Caribou Biosciences common stock at an exercise price of $0.00 per share. The option vests monthly over four years, becoming fully vested by February 20, 2030, subject to continued service.

What restricted stock unit (RSU) grant did CRBU’s CFO report?

The filing shows a grant of 55,000 RSUs to the CFO. These RSUs vest in four equal annual installments starting February 20, 2027, if he continues providing service, and are settled in stock within 30 days after each vesting date.

Are these Caribou Biosciences insider transactions open-market purchases or equity awards?

These transactions are equity awards, not open-market purchases. Both the 247,500-share option and the 55,000-share RSU grant are reported with a price of $0.00 per share and are described as grants or awards subject to vesting conditions based on continued service.

When will the Caribou Biosciences RSUs granted to the CFO fully vest?

The 55,000 RSUs granted to the CFO vest in four equal annual installments beginning February 20, 2027. Assuming continued service through each vesting date, the RSUs will be fully vested after the fourth installment and settled in stock within 30 days after each vest.

What is the vesting schedule for the Caribou Biosciences stock options granted to the CFO?

The 247,500-share stock option vests in 48 equal monthly installments. One forty-eighth of the total vests on each monthly anniversary of the grant date, so the option is fully vested by February 20, 2030, provided the CFO continues to provide service throughout the vesting period.