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Gossamer Bio (GOSS) 10K Form and Latest SEC Filings 2026

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Closing price 05/22/2026 04:00 PM Eastern
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Latest Gossamer Bio SEC Filings & Recent Activity

Gossamer Bio (NASDAQ:GOSS) has submitted 264+ documents to the U.S. Securities and Exchange Commission (SEC) since 2018. For investors, these filings are the primary source of verified financial data — covering everything from annual revenue and debt levels in the 10-K, to material business events in 8-K current reports, to insider buying and selling activity in Form 4 disclosures. The most recent filing was a Form PRE 14A submitted on May 18, 2026.

Form 4
Gossamer Bio, Inc. Reports Ownership Change on Mar. 20, 2026

Form 4 filings disclose changes in stock ownership by company insiders, including purchases, sales, grants, and option exercises.

View insider ownership

8-K
Gossamer Bio Files Current Report on May. 18, 2026

An 8-K is filed when a material corporate event occurs, such as an acquisition, leadership change, or financial update.

View filing

10-Q
Gossamer Bio Files Quarterly Report on Nov. 5, 2025

The 10-Q contains Gossamer Bio's unaudited quarterly financial statements, revenue, earnings updates, and cash flow changes between annual reports.

View earnings history

Gossamer Bio SEC Filing History

Browse Gossamer Bio's complete SEC filing history using the filters below. Filter by form type - 10-K, 10-Q, 8-K, Form 4, and more - or set a custom date range to find a filing.

DateFilerForm TypeView
05/18/2026 6:07 AM
Gossamer Bio (1728117) Filer
Form DEFA14A
05/18/2026 6:08 AM
Gossamer Bio (1728117) Filer
Form PRE 14A
05/18/2026 6:06 AM
Gossamer Bio (1728117) Filer
Form 8-K
Current report pursuant to Section 13 or 15(d)  
04/24/2026 3:03 PM
Gossamer Bio (1728117) Filer
Form ARS
04/09/2026 3:01 PM
Gossamer Bio (1728117) Filer
Form 8-K
Current report pursuant to Section 13 or 15(d)  
03/27/2026 8:31 AM
Gossamer Bio (1728117) Subject
VANGUARD GROUP INC (102909) Filed by
Form SCHEDULE 13G/A
03/24/2026 3:48 PM
683 Capital Management, LLC (1404574) Filed by
Gossamer Bio (1728117) Subject
Form SCHEDULE 13G/A
03/20/2026 3:20 PM
Gossamer Bio (1728117) Issuer
Peterson Caryn (1857256) Reporting
Form 4
Statement of changes in beneficial ownership of securities  
03/20/2026 3:22 PM
Aranda Richard (1867872) Reporting
Gossamer Bio (1728117) Issuer
Form 4
Statement of changes in beneficial ownership of securities  
03/20/2026 3:14 PM
Christian Waage (1553179) Reporting
Gossamer Bio (1728117) Issuer
Form 4
Statement of changes in beneficial ownership of securities  
03/18/2026 11:15 PM
Gossamer Bio (1728117) Filer
Form EFFECT
03/02/2026 10:57 AM
683 Capital Management, LLC (1404574) Filed by
Gossamer Bio (1728117) Subject
Form SCHEDULE 13G
02/24/2026 6:21 PM
Gossamer Bio (1728117) Subject
Growth Equity Opportunities 18 VGE, LLC (1917895) Filed by
Form SCHEDULE 13D/A
02/23/2026 7:30 AM
Gossamer Bio (1728117) Filer
Form 8-K
Current report pursuant to Section 13 or 15(d)  
01/05/2026 3:35 PM
Christian Waage (1553179) Reporting
Gossamer Bio (1728117) Issuer
Form 4
Statement of changes in beneficial ownership of securities  
01/05/2026 3:37 PM
Gossamer Bio (1728117) Issuer
Peterson Caryn (1857256) Reporting
Form 4
Statement of changes in beneficial ownership of securities  
11/05/2025 4:23 PM
Gossamer Bio (1728117) Filer
Form 10-Q
General form for quarterly reports under Section 13 or 15(d)  
11/05/2025 4:23 PM
Gossamer Bio (1728117) Filer
Form 8-K
Current report pursuant to Section 13 or 15(d)  
09/25/2025 7:50 AM
Gossamer Bio (1728117) Filer
Form 8-K
Current report pursuant to Section 13 or 15(d)  
08/20/2025 3:04 PM
Gossamer Bio (1728117) Issuer
Milligan Sandra (1859810) Reporting
Form 4
Statement of changes in beneficial ownership of securities  
07/29/2025 12:34 PM
Gossamer Bio (1728117) Subject
VANGUARD GROUP INC (102909) Filed by
Form SCHEDULE 13G
07/17/2025 6:54 PM
BlackRock, Inc. (2012383) Filed by
Gossamer Bio (1728117) Subject
Form SCHEDULE 13G
06/26/2025 3:40 PM
Daniel Thomas O (1538894) Reporting
Gossamer Bio (1728117) Issuer
Form 4
Statement of changes in beneficial ownership of securities  
06/26/2025 3:35 PM
Drynan Skye (2015102) Reporting
Gossamer Bio (1728117) Issuer
Form 4
Statement of changes in beneficial ownership of securities  
06/26/2025 3:36 PM
Gossamer Bio (1728117) Issuer
Milligan Sandra (1859810) Reporting
Form 4
Statement of changes in beneficial ownership of securities  
06/26/2025 3:37 PM
Gossamer Bio (1728117) Issuer
Quisel John D (1586788) Reporting
Form 4
Statement of changes in beneficial ownership of securities  
06/26/2025 3:38 PM
Cox Russell J. (1512984) Reporting
Gossamer Bio (1728117) Issuer
Form 4
Statement of changes in beneficial ownership of securities  
06/26/2025 3:39 PM
Gossamer Bio (1728117) Issuer
Nathan Steven D (2015114) Reporting
Form 4
Statement of changes in beneficial ownership of securities  
06/25/2025 3:01 PM
Gossamer Bio (1728117) Filer
Form 8-K
Current report pursuant to Section 13 or 15(d)  
06/16/2025 6:31 AM
Gossamer Bio (1728117) Filer
Form 8-K
Current report pursuant to Section 13 or 15(d)  
(Data available from 1/1/2016 forward)

Gossamer Bio SEC Filings - Frequently Asked Questions

Gossamer Bio (GOSS) has submitted 264+ filings to the SEC since 2018. You can browse the complete history or filter by form type using the tools above.

Gossamer Bio's fiscal year ends on December 31. The company typically files its 10-K annual report by the end of February, covering the prior fiscal year's financial results.

The most recent filing was a Form PRE 14A submitted on May 18, 2026. View the full filing using the link above.

SEC Filing Types: 10-K, 10-Q, 8-K and More

SEC filings are legally required disclosures that public companies submit to the U.S. Securities and Exchange Commission. Unlike press releases or earnings call transcripts, these documents are filed under legal obligation — meaning the financial data they contain is audited, standardized, and subject to penalties if materially false. For investors, that makes SEC filings the most reliable primary source available for evaluating a company's true financial position.

Yes. All SEC filings are publicly available through the SEC's EDGAR database and on financial research platforms like MarketBeat. Companies are required by law to make these disclosures accessible to all investors — meaning retail investors have access to the same source documents as institutional analysts.

A 10-K is an annual report containing audited financial statements and a full review of the company's business — it is the most comprehensive filing a company makes each year. A 10-Q is a shorter, unaudited quarterly update filed three times per year between annual reports. Investors typically use the 10-K for deep fundamental analysis and the 10-Q to track whether the company is on pace with its guidance mid-year.

The most important filing for fundamental investors. Filed once per year, the 10-K contains audited financial statements, revenue and earnings trends, debt obligations, risk factors, and management's own assessment of the business. Reading the risk factors section and comparing year-over-year financials can reveal issues that don't show up in analyst summaries.

An unaudited financial update filed three times per year (the 10-K covers Q4). Investors use 10-Qs to track whether guidance is on pace, monitor changes in cash flow or inventory, and catch any mid-year shifts in business conditions before they become headline news.

Filed within four business days of a material event — earnings releases, merger announcements, executive departures, or major asset sales. Because 8-Ks are filed before media coverage catches up, they are often the fastest way to get unfiltered information directly from the company on market-moving events.

Filed within two business days whenever an executive or director buys or sells company stock. Insider purchases — especially large or clustered buys — are often interpreted as a signal of management confidence. Insider selling is more ambiguous but worth monitoring for patterns, particularly around lock-up expirations or ahead of major announcements.


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This page (NASDAQ:GOSS) was last updated on 5/26/2026 by MarketBeat.com Staff.
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