---
schema_version: "secwatch.filing_event.v1"
accession: "0001728117-26-000036"
form_type: "8-K"
ticker: "GOSS"
cik: "0001728117"
company_name: "Gossamer Bio, Inc."
filed_at: "2026-05-18T11:06:58+00:00"
generated_at: "2026-05-18T11:11:47.921706+00:00"
event_type: "debt"
sentiment: "neutral"
materiality_score: 0.85
calibrated_materiality_score: 0.85
confidence: "high"
source: SEC EDGAR
---

# Gossamer Bio launches exchange offer for 5.00% notes; holders of 75.2% support

## Summary
- Exchange Offer: up to $72M new 7.50% Convertible Secured Notes due 2030, plus up to 317.6M common shares and 150M Purchase Warrants.
- Supporting Noteholders holding 75.2% of existing notes agree to tender and consent to indenture amendments.
- Conditions include minimum 98% participation; early settlement expected June 3, final June 18, 2026.
- Also filed Q1 2026 financial results (press release not provided in filing text).
- Stockholder proposals include increasing authorized shares from 700M to 4B and reverse stock split (1:10 to 1:150).

## SEC filing metadata
- accession: 0001728117-26-000036
- form_type: 8-K
- ticker: GOSS
- cik: 0001728117
- company_name: Gossamer Bio, Inc.
- filed_at: 2026-05-18T11:06:58+00:00
- event_type: debt
- sentiment: neutral
- materiality_score: 0.85
- calibrated_materiality_score: 0.85
- confidence: high
- sec_items: 1.01, 2.02, 5.02, 7.01, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1728117/000172811726000036/0001728117-26-000036-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1728117/000172811726000036/goss-20260518.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001728117-26-000036
- JSON: https://secwatch.observer/filing/0001728117-26-000036.json
- Plain text: https://secwatch.observer/filing/0001728117-26-000036.txt

## Key facts
- Earnings Releases
  Gossamer Bio, Inc. reported financial results for the quarter ended March 31, 2026.
  - Period: the quarter ended March 31, 2026
  - Result: reported results
  source text: On May 18, 2026, the Company issued a press release reporting its financial results for the quarter ended March 31, 2026.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1728117/000172811726000036/0001728117-26-000036-index.htm
- Material Agreements
  Gossamer Bio, Inc. entered into Transaction Support Agreement with Supporting Noteholders valued at Certain beneficial owners or nominees, investment managers or advisors for beneficial holders of the (effective 2026-05-18).
  - Action: entry
  - Agreement: notes offering
  - Counterparty: Supporting Noteholders
  - Value: Certain beneficial owners or nominees, investment managers or advisors for beneficial holders of the
  - Effective: 2026-05-18
  source text: On May 18, 2026, the Company entered into a transaction support agreement (the "Transaction Support Agreement") with certain beneficial owners or nominees, investment managers or advisors for beneficial holders of the Existing Convertible Notes who hold approximately 75.2% of the aggregate principal amount of the Existing Convertible Notes (the "Supporting Noteholders").
  evidence_url: https://www.sec.gov/Archives/edgar/data/1728117/000172811726000036/0001728117-26-000036-index.htm

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.