Form 4: Lynx1/Weston Nichols Reports 32,008 PASG Shares Acquired in Sept 2025

Rhea-AI Filing Summary

Passage BIO, Inc. (PASG) Form 4: Lynx1 Capital Management LP and Weston Nichols reported insider purchases of Passage BIO common stock on three dates in September 2025. The filings show acquisitions of 325 shares on 09/11/2025 at a weighted average price of $6.9558 (range $6.915–$6.985), 19,783 shares on 09/12/2025 at $6.9908 (range $6.93–$7.00), and 11,900 shares on 09/15/2025 at $6.9895 (range $6.94–$7.00). Following these transactions, the filing reports beneficial ownership of 623,704 shares held indirectly through Lynx1 Master Fund LP, for which Lynx1 Capital Management LP is the investment manager and Weston Nichols is the sole member of the manager's GP. The reporting persons are identified as a director and a 10% owner.

Positive

• Incremental purchases disclosed: 32,008 shares acquired across three dates, demonstrating clear transaction reporting
• Beneficial ownership reported: Indirect holdings disclosed at 623,704 shares following the transactions
• Price transparency: Weighted-average prices provided with footnote ranges and offer to supply per-trade breakdowns on request
• Proper disclosure of ownership structure: Identifies Lynx1 Master Fund LP as direct holder and Lynx1 Capital Management LP and Weston Nichols roles

Negative

• None.

Insights

Securities Analyst

TL;DR: Reporting persons executed multiple open-market purchases, increasing indirect beneficial ownership to 623,704 shares.

The Form 4 discloses aggregated acquisitions on 09/11, 09/12 and 09/15/2025 totaling 32,008 shares, with weighted-average prices disclosed and per-footnote price ranges provided. The shares are held indirectly by Lynx1 Master Fund LP, for which Lynx1 Capital Management LP is investment manager; Weston Nichols is affiliated as sole member of the GP. No derivative positions are reported. For investors tracking insider activity, these are straightforward buy transactions increasing reported indirect holdings.

Corporate Governance Expert

TL;DR: Filing clearly discloses beneficial ownership structure and incremental purchases by an affiliated investment manager.

The disclosure includes the required clarifying statements: indirect ownership through Lynx1 Master Fund LP, the manager relationship, and a disclaimer of beneficial ownership except to the extent of pecuniary interest. Footnotes supply weighted-average price ranges and the offer to provide per-transaction price breakdowns on request, which aligns with Form 4 transparency expectations. Signatures from the manager and Weston Nichols appear on 09/15/2025, completing the procedural requirements.

Insider Trade Summary

Net Buyer: 32,008 shares ($223,735)

Net Buy 3 txns

Insider Lynx1 Capital Management LP, Nichols Weston

Role 10% Owner | 10% Owner

Bought 32,008 shs ($224K)

Type	Security	Shares	Price	Value
Purchase	Common Stock	11,900	$6.9895	$83K
Purchase	Common Stock	19,783	$6.9908	$138K
Purchase	Common stock, $0.0001 par value per share (Common Stock)	325	$6.9558	$2K

Holdings After Transaction: Common Stock — 623,704 shares (Indirect, See footnote); Common stock, $0.0001 par value per share (Common Stock) — 592,021 shares (Indirect, See footnote)

Footnotes (1)

1. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $6.915 to $6.985 inclusive. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission (the "SEC"), upon request, full information regarding the number of shares purchased at each separate price within the range set forth herein. 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. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $6.93 to $7.00 inclusive. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer, or the staff of the SEC, upon request, full information regarding the number of shares purchased at each separate price within the range set forth herein. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $6.94 to $7.00 inclusive. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer, or the staff of the SEC, upon request, full information regarding the number of shares purchased at each separate price within the range set forth herein.

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).

1. Name and Address of Reporting Person^*

Lynx1 Capital Management LP

(Last) (First) (Middle)

D81 CALLE C

SUITE 301, PMB 1202

(Street)

DORADO PR 00646-2051

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Passage BIO, Inc. [ PASG ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
09/11/2025

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

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

	Form filed by One Reporting Person
X	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, $0.0001 par value per share (Common Stock)	09/11/2025		P		325	A	$6.9558(1)	592,021	I	See footnote(2)
Common Stock	09/12/2025		P		19,783	A	$6.9908(3)	611,804	I	See footnote(2)
Common Stock	09/15/2025		P		11,900	A	$6.9895(4)	623,704	I	See footnote(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

1. Name and Address of Reporting Person^*

Lynx1 Capital Management LP

(Last) (First) (Middle)

D81 CALLE C

SUITE 301, PMB 1202

(Street)

DORADO PR 00646-2051

(City) (State) (Zip)

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 PR 00646-2051

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

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

Explanation of Responses:

1. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $6.915 to $6.985 inclusive. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission (the "SEC"), upon request, full information regarding the number of shares purchased at each separate price within the range set forth herein.

2. 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.

3. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $6.93 to $7.00 inclusive. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer, or the staff of the SEC, upon request, full information regarding the number of shares purchased at each separate price within the range set forth herein.

4. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $6.94 to $7.00 inclusive. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer, or the staff of the SEC, upon request, full information regarding the number of shares purchased at each separate price within the range set forth herein.

	Lynx1 Capital Management LP, By: Lynx1 Capital Management GP LLC, its general partner, By: /s/ Weston Nichols, Sole Member	09/15/2025
	/s/ Weston Nichols	09/15/2025
	** 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 were reported for PASG on this Form 4?

The Form 4 reports purchases of 325 shares on 09/11/2025, 19,783 shares on 09/12/2025, and 11,900 shares on 09/15/2025, totaling 32,008 shares.

How many PASG shares are beneficially owned after these transactions?

The filing reports indirect beneficial ownership of 623,704 shares following the reported transactions.

At what prices were the PASG shares purchased?

Weighted-average prices reported are $6.9558 on 09/11/2025, $6.9908 on 09/12/2025, and $6.9895 on 09/15/2025; footnotes show per-trade ranges.

Who holds the shares and what is the ownership relationship?

The shares are held directly by Lynx1 Master Fund LP; Lynx1 Capital Management LP is the investment manager and Weston Nichols is the sole member of the manager's GP.

Were any derivative securities reported on this Form 4?

No derivative securities are reported in Table II of the filing.