# EDGAR Filing Document

**Accession Number:** 0001728117
**File Stem:** 9999999995-26-000860
**Filing Date:** 2026-3
**Character Count:** 1339
**Document Hash:** c9f65be43a064db797b87e418e5e4bdd
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**9999999995-26-000860.hdr.sgml**: 20260319

**ACCESSION NUMBER**: 9999999995-26-000860

**CONFORMED SUBMISSION TYPE**: EFFECT

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20260318

**DATE AS OF CHANGE**: 20260319

**EFFECTIVENESS DATE**: 20260318

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Gossamer Bio, Inc.
- **CENTRAL INDEX KEY:** 0001728117
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 475461709
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** EFFECT
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-293009
- **FILM NUMBER:** 26772218

**BUSINESS ADDRESS:**
- **STREET 1:** 3115 MERRYFIELD ROW
- **STREET 2:** SUITE 120
- **CITY:** SAN DIEGO
- **STATE:** CA
- **ZIP:** 92121
- **BUSINESS PHONE:** (858) 684-1300

**MAIL ADDRESS:**
- **STREET 1:** 3115 MERRYFIELD ROW
- **STREET 2:** SUITE 120
- **CITY:** SAN DIEGO
- **STATE:** CA
- **ZIP:** 92121

### UNITED STATES
### SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## Notice of Effectiveness

**Date:** March 18, 2026

**Accession Number:** 0001728117-26-000020

**Form Type:** POS AM

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**CIK:** 0001728117

**Company Name:** Gossamer Bio, Inc.

**File Number:** 333-293009