Statement of Changes in Beneficial Ownership (Form 4)

FORM 4 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 that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person * Smith Robert Paul JR 2. Issuer Name and Ticker or Trading Symbol Gossamer Bio, Inc. [GOSS] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) Chief Commercial Officer (Last) (First) (Middle) 3115 MERRYFIELD ROW, SUITE 120 3. Date of Earliest Transaction (Month/Day/Year) 03/19/2026 (Street) SAN DIEGO, CA 92121 4. If Amendment, Date 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 (City) (State) (Zip) 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

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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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 Underlying Securities (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 of Derivative Security: 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)

$2.88

03/19/2026

D(1)

562,500

(2)

01/01/2036

Common Stock

562,500

(1)

0

D

Stock Option (Right to Buy)

$1.13

03/19/2026

D(1)

572,000

(2)

03/03/2035

Common Stock

572,000

(1)

0

D

Stock Option (Right to Buy)

$0.45

03/19/2026

A(1)

562,500

(2)

01/01/2036

Common Stock

562,500

(1)

562,500

D

Stock Option (Right to Buy)

$0.45

03/19/2026

A(1)

572,000

(2)

03/03/2035

Common Stock

572,000

(1)

572,000

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Smith Robert Paul JR 3115 MERRYFIELD ROW, SUITE 120 SAN DIEGO, CA 92121			Chief Commercial Officer

Signatures

/s/ Jeff Boerneke, Attorney-in-Fact		03/20/2026
**Signature of Reporting Person		Date

Explanation of Responses:

*	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).
(1)	Effective as of March 19, 2026 (the "Repricing Date"), the Issuer approved a one-time repricing of certain outstanding stock options (the "Repriced Options") granted under the Issuer's 2019 Incentive Award Plan (the "2019 Plan"), which reduced the per share exercise price of each Repriced Option to $0.45 (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the Repriced Options, including, without limitation, any provisions with respect to vesting and term of the Repriced Options, remain in full force and effect.
(2)	This stock option award was issued pursuant to the 2019 Plan and becomes exercisable in accordance with the vesting schedule specified in the award agreement and as previously reported on applicable Form 4, subject to the Reporting Person's continued service with the Issuer as of the applicable vesting date.

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