<SEC-DOCUMENT>0001728117-23-000053.txt : 20230509
<SEC-HEADER>0001728117-23-000053.hdr.sgml : 20230509
<ACCEPTANCE-DATETIME>20230509161500
ACCESSION NUMBER:		0001728117-23-000053
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20230505
FILED AS OF DATE:		20230509
DATE AS OF CHANGE:		20230509

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Giraudo Bryan
		CENTRAL INDEX KEY:			0001740847

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38796
		FILM NUMBER:		23902186

	MAIL ADDRESS:	
		STREET 1:		7707 GATEWAY BOULEVARD, SUITE 140
		CITY:			NEWARK
		STATE:			CA
		ZIP:			94560

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Gossamer Bio, Inc.
		CENTRAL INDEX KEY:			0001728117
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				475461709
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		3013 SCIENCE PARK
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92121
		BUSINESS PHONE:		(858) 922-0718

	MAIL ADDRESS:	
		STREET 1:		3013 SCIENCE PARK
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92121
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>FORM 4
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            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92121</rptOwnerZipCode>
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    <footnotes>
        <footnote id="F1">The shares subject to the option are fully vested.</footnote>
        <footnote id="F2">On May 5, 2023, the Issuer canceled an option granted on March 25, 2019. In exchange for the canceled option, the reporting person received 96,667 options to purchase common stock having a lower exercise price with the same vesting terms.</footnote>
        <footnote id="F3">25% of the total number of shares subject to the option vested on February 14, 2021 and 1/48th of the total number of shares subject to the option vest on the last day of each one-month period thereafter, subject to the Reporting Person's continuous service to the Issuer on each such vesting date.</footnote>
        <footnote id="F4">On May 5, 2023, the Issuer canceled an option granted on February 14, 2020. In exchange for the canceled option, the reporting person received 47,667 options to purchase common stock having a lower exercise price with the same vesting terms.</footnote>
        <footnote id="F5">25% of the total number of shares subject to the option vested on February 25, 2022 and 1/48th of the total number of shares subject to the option vest on the last day of each one-month period thereafter, subject to the Reporting Person's continuous service to the Issuer on each such vesting date.</footnote>
        <footnote id="F6">On May 5, 2023, the Issuer canceled an option granted on February 25, 2021. In exchange for the canceled option, the reporting person received 60,000 options to purchase common stock having a lower exercise price with the same vesting terms.</footnote>
        <footnote id="F7">25% of the total number of shares subject to the option vested on September 16, 2022 and 1/48th of the total number of shares subject to the option vest on the last day of each one-month period thereafter, subject to the Reporting Person's continuous service to the Corporation on each such vesting date.</footnote>
        <footnote id="F8">On May 5, 2023, the Issuer canceled an option granted on September 16, 2021. In exchange for the canceled option, the reporting person received 100,000 options to purchase common stock having a lower exercise price with the same vesting terms.</footnote>
        <footnote id="F9">One-third of the total number of shares subject to the option vested on January 6, 2023 and 1/36th of the total number of shares subject to the option vest on the last day of each one-month period thereafter, subject to the Reporting Person's continuous service to the Issuer on each such vesting date.</footnote>
        <footnote id="F10">On May 5, 2023, the Issuer canceled an option granted on January 6, 2022. In exchange for the canceled option, the reporting person received 176,677 options to purchase common stock having a lower exercise price with the same vesting terms.</footnote>
        <footnote id="F11">The exercise price of the option is $1.36 per share, representing the fair market value per share of the Issuer's common stock on the date of grant; provided that in the event the option is exercised prior to May 5, 2024, or the Reporting Person's employment terminates prior to May 5, 2024 other than due to death, disability or circumstances giving rise to severance under the Reporting Person's employment agreement, the exercise price will be increased to the exercise price of the cancelled option in exchange for which this option was granted.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Jeff Boerneke, Attorney-in-Fact</signatureName>
        <signatureDate>2023-05-09</signatureDate>
    </ownerSignature>
</ownershipDocument>
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