Ram Aiyar - 02 Feb 2026 Form 4 Insider Report for Korro Bio, Inc. (KRRO)

Reporting relationship: President and CEO, Director
Issuer ticker: KRRO
Reported as of: 02 Feb 2026
Net transaction value: $0
SEC form: 4
Accepted by SEC: 03 Feb 2026, 16:17:03 UTC
Prior SEC filing: 05 Feb 2025
Next SEC filing: 28 May 2026
Source filing: View source filing
Reporting owner signature: /s/ Jeffrey Cerio, Attorney-in-fact

Key filing fact

Ram Aiyar filed Form 4 for Korro Bio, Inc. (KRRO) on 03 Feb 2026.

Key facts

This page summarizes Ram Aiyar's Form 4 filing for Korro Bio, Inc. (KRRO).
2 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 03 Feb 2026, 16:17.

Change

Previous filing in this sequence was filed on 05 Feb 2025.
Current net transaction value: $0.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001997920 Primary reporting owner

Aiyar Ram

Relationship: President and CEO, Director
Address: C/O KORRO BIO, INC., 60 FIRST STREET, 2ND FLOOR, SUITE 250, CAMBRIDGE
Signature: /s/ Jeffrey Cerio, Attorney-in-fact
Signature date: 03 Feb 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

KRRO transaction

Common Stock

Award

Transaction value: $0
Shares: +40,000
Change %
Price: $0.000000
Shares after: 40,000
Date: 02 Feb 2026
Ownership: Direct
Footnotes: F1

KRRO holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 4,613
Date: 02 Feb 2026
Ownership: Shares are held by The Ram Aiyar Irrevocable Trust.
Footnotes: F2

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

KRRO transaction Derivative

Stock Option (Right to Buy)

Award

Transaction value: $0
Shares: +80,000
Change %
Price: $0.000000
Shares after: 80,000
Date: 02 Feb 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 80,000
Exercise price: $13.05
Footnotes: F3

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 3 footnotes

Footnote F1

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.

Footnote F2

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.

Footnote F3

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.