Korro Bio (KRRO) CEO granted 80K options, 40K RSUs

Rhea-AI Filing Summary

Korro Bio, Inc. reported that President and CEO Ram Aiyar received new equity awards on February 2, 2026. He was granted 40,000 shares of common stock through restricted stock units under the 2023 Stock Option and Incentive Plan, vesting 50% on August 3, 2026 and 50% on February 1, 2027, subject to continued service.

He was also granted a stock option for 80,000 shares of common stock at an exercise price of $13.05, vesting in 48 equal monthly installments starting February 2, 2026 and expiring February 1, 2036. Separately, 4,613 common shares are held indirectly by The Ram Aiyar Irrevocable Trust, for which he serves as trustee and disclaims full beneficial ownership.

Insider Trade Summary

3 transactions reported

Mixed 3 txns

Insider Aiyar Ram

Role President and CEO

Type	Security	Shares	Price	Value
Grant/Award	Stock Option (Right to Buy)	80,000	$0.00	--
Grant/Award	Common Stock	40,000	$0.00	--
holding	Common Stock	--	--	--

Holdings After Transaction: Stock Option (Right to Buy) — 80,000 shares (Direct); Common Stock — 40,000 shares (Direct); Common Stock — 4,613 shares (Indirect, Shares are held by The Ram Aiyar Irrevocable Trust.)

Footnotes (1)

1. Represents shares of common stock issuable upon settlement of a restricted stock unit (RSU) granted under the Issuer's 2023 Stock Option and Incentive Plan (the 2023 Plan) that will vest as follows: 50% on August 3, 2026 and 50% on February 1, 2027, in each case subject to the Reporting Person's continued service on each such vesting date. Shares held by The Ram Aiyar Irrevocable Trust, for which the Reporting Person serves as trustee. The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of all of the reported shares for purposes of Section 16 or for any other purpose. The shares subject to the option vest in 48 equal monthly installments commencing from February 2, 2026, subject to the Reporting Person's continued service on 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^*

Aiyar Ram

(Last) (First) (Middle)

C/O KORRO BIO, INC.

60 FIRST STREET, 2ND FLOOR, SUITE 250

(Street)

CAMBRIDGE MA 02141

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Korro Bio, Inc. [ KRRO ]

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

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	President and CEO

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

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	02/02/2026		A		40,000(1)	A	$0.00	40,000	D
Common Stock								4,613	I	Shares are held by The Ram Aiyar Irrevocable Trust.(2)

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
Stock Option (Right to Buy)	$13.05	02/02/2026		A		80,000		(3)	02/01/2036	Common Stock	80,000	$0	80,000	D

Explanation of Responses:

1. Represents shares of common stock issuable upon settlement of a restricted stock unit (RSU) granted under the Issuer's 2023 Stock Option and Incentive Plan (the 2023 Plan) that will vest as follows: 50% on August 3, 2026 and 50% on February 1, 2027, in each case subject to the Reporting Person's continued service on each such vesting date.

2. Shares held by The Ram Aiyar Irrevocable Trust, for which the Reporting Person serves as trustee. The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of all of the reported shares for purposes of Section 16 or for any other purpose.

3. The shares subject to the option vest in 48 equal monthly installments commencing from February 2, 2026, subject to the Reporting Person's continued service on each such vesting date.

	/s/ Jeffrey Cerio, Attorney-in-fact	02/03/2026
	** 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 equity awards did Korro Bio (KRRO) grant to CEO Ram Aiyar on February 2, 2026?

Korro Bio granted CEO Ram Aiyar 40,000 RSUs and a stock option for 80,000 shares on February 2, 2026. The RSUs and options were issued under the 2023 Stock Option and Incentive Plan with multi-year vesting tied to his continued service.

How do Ram Aiyar’s 40,000 Korro Bio (KRRO) RSUs vest?

The 40,000 RSUs for Ram Aiyar vest in two equal tranches. Half vests on August 3, 2026 and the remaining half on February 1, 2027, in each case conditioned on his continued service through the applicable vesting date.

What are the key terms of Ram Aiyar’s 80,000 Korro Bio (KRRO) stock options?

Ram Aiyar’s option covers 80,000 Korro Bio common shares at a $13.05 exercise price. It vests in 48 equal monthly installments starting February 2, 2026 and expires on February 1, 2036, assuming his continued service for each vesting date.

Does Ram Aiyar hold any Korro Bio (KRRO) shares indirectly through a trust?

Yes. 4,613 Korro Bio common shares are held by The Ram Aiyar Irrevocable Trust. He serves as trustee and disclaims beneficial ownership of these securities except to the extent of his pecuniary interest, as noted in the filing footnote.

Is Ram Aiyar’s Form 4 filing for Korro Bio (KRRO) a purchase of shares?

No. The Form 4 reflects equity grants, not open-market purchases. It reports 40,000 RSUs and an option for 80,000 shares granted at no cost on the grant date, with future vesting and, for options, an exercise price of $13.05 per share.

What corporate roles does Ram Aiyar hold at Korro Bio (KRRO) according to the Form 4?

Ram Aiyar is listed as both a director and an officer of Korro Bio. His officer title is President and CEO, which is relevant because Form 4 specifically discloses equity transactions by directors and executive officers subject to Section 16 reporting rules.