Lynx1 fund tied to Weston Nichols adds Korro Bio (KRRO) position

Rhea-AI Filing Summary

Lynx1 Master Fund LP, an entity associated with Lynx1 Capital Management LP and Weston Nichols, reported an indirect open-market purchase of 520 shares of Korro Bio, Inc. common stock at $10.60 per share. Following this transaction, the reporting structure shows 1,538,296 shares held indirectly. Lynx1 Capital Management LP and Mr. Nichols each disclaim beneficial ownership except to the extent of any pecuniary interest.

Insider Trade Summary

Net Buyer: 520 shares ($5,512)

Net Buy 1 txn

Insider Lynx1 Capital Management LP, Nichols Weston

Role 10% Owner | 10% Owner

Bought 520 shs ($6K)

Type	Security	Shares	Price	Value
Purchase	Common stock, $0.001 par value per share	520	$10.60	$6K

Holdings After Transaction: Common stock, $0.001 par value per share — 1,538,296 shares (Indirect, See footnote)

Footnotes (1)

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Key Figures

Shares purchased: 520 shares Purchase price: $10.60 per share Indirect holdings after trade: 1,538,296 shares +1 more

4 metrics

Shares purchased 520 shares Open-market purchase of common stock

Purchase price $10.60 per share Price for non-derivative open-market transaction

Indirect holdings after trade 1,538,296 shares Total common stock held indirectly following transaction

Net buy shares 520 shares Net change in position from this Form 4

Key Terms

open-market purchase, indirect ownership, beneficial ownership, pecuniary interest

4 terms

open-market purchase financial

"transaction_action: "open-market purchase""

An open-market purchase is when an investor or a company buys shares on a public stock exchange at the going market price, rather than through a private deal. It matters to investors because these purchases change how many shares are available, can push the stock price up or signal confidence from large buyers, and often affect per-share metrics like earnings—think of it like someone buying lots of apples off a grocery shelf, reducing supply and potentially raising the price.

indirect ownership financial

"direct_or_indirect: "I" and ownership_type: "indirect""

beneficial ownership financial

"disclaims beneficial ownership of the securities to which this filing relates"

Beneficial ownership means the person or entity that actually enjoys the benefits of owning shares or other assets — such as receiving dividends, voting rights, or price gains — even if the legal title is held in another name. For investors it matters because knowing who truly controls and profits from a company reveals who can influence decisions, exposes potential conflicts of interest or hidden concentration of power, and affects transparency and risk in the stock.

pecuniary interest financial

"except to the extent of his or its pecuniary interest therein"

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^*

Lynx1 Capital Management LP

(Last) (First) (Middle)

D81 CALLE C

SUITE 301 PMB 1202

(Street)

DORADO PUERTO RICO 00646-2051

(City) (State) (Zip)

UNITED STATES

(Country)

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

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

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
03/31/2026

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

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

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

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, $0.001 par value per share	03/31/2026		P		520	A	$10.6	1,538,296	I	See footnote(1)

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

1. Name and Address of Reporting Person^*

Lynx1 Capital Management LP

(Last) (First) (Middle)

D81 CALLE C

SUITE 301 PMB 1202

(Street)

DORADO PUERTO RICO 00646-2051

(City) (State) (Zip)

UNITED STATES

(Country)

Relationship of Reporting Person(s) to Issuer

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

1. Name and Address of Reporting Person^*

Nichols Weston

(Last) (First) (Middle)

D81 CALLE C

SUITE 301 PMB 1202

(Street)

DORADO PUERTO RICO 00646-2051

(City) (State) (Zip)

UNITED STATES

(Country)

Relationship of Reporting Person(s) to Issuer

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

Explanation of Responses:

1. The securities to which this filing relates are held directly by Lynx1 Master Fund LP to which Lynx1 Capital Management LP (the "Investment Manager") serves as investment manager. Weston Nichols ("Mr. Nichols") is the sole member of Lynx1 Capital Management GP LLC, the general partner of the Investment Manager. Each of the Investment Manager and Mr. Nichols disclaims beneficial ownership of the securities to which this filing relates for purposes of Section 16 of the Securities and Exchange Act of 1934, as amended, except to the extent of his or its pecuniary interest therein, if any.

	Lynx1 Capital Management LP, By: Lynx1 Capital Management GP LLC, its general partner, By: /s/ Weston Nichols, Sole Member	04/02/2026
	/s/ Weston Nichols	04/02/2026
	** 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.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transaction did Korro Bio (KRRO) report in this Form 4?

Korro Bio reported an indirect open-market purchase of 520 common shares at $10.60 each. The shares are held by Lynx1 Master Fund LP, linked to Lynx1 Capital Management LP and Weston Nichols, increasing the reported indirect holdings to 1,538,296 shares.

Who is the reporting person in the Korro Bio (KRRO) Form 4 filing?

The filing lists Lynx1 Capital Management LP and Weston Nichols as reporting persons and ten percent owners. The securities are held directly by Lynx1 Master Fund LP, for which Lynx1 Capital Management LP serves as investment manager, with each party disclaiming full beneficial ownership.

How many Korro Bio (KRRO) shares were purchased and at what price?

The Form 4 shows an indirect open-market purchase of 520 shares of Korro Bio common stock at a price of $10.60 per share. This transaction is categorized as a non-derivative acquisition of common stock with a standard open-market purchase code P.

What are the total Korro Bio (KRRO) shares held after this insider trade?

After the reported transaction, indirect holdings stand at 1,538,296 Korro Bio common shares. This total reflects the position attributed to the reporting structure following the 520-share open-market purchase disclosed in the filing’s non-derivative transaction table.

How is beneficial ownership described in the Korro Bio (KRRO) Form 4 footnote?

The footnote states that Lynx1 Master Fund LP holds the securities directly, with Lynx1 Capital Management LP as investment manager. Lynx1 Capital Management LP and Weston Nichols each disclaim beneficial ownership except to the extent of any pecuniary interest they may have in the securities.