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AI Earnings Predictions for Gossamer Bio Inc. (GOSS)

Machine learning predictions based on historical earnings data and price patterns

Latest Prediction

BUY

1-Day Prediction

+4.18%

$11.77

100% positive prob.

5-Day Prediction

+15.34%

$13.03

100% positive prob.

20-Day Prediction

+13.32%

$12.81

95% positive prob.

Price at prediction: $11.30 Confidence: 100.0% Model AUC: 1.0000 Quarter: Q3 2026

Historical Earnings Predictions

Quarter Signal 1D Return 5D Return 20D Return Confidence Actual 5D
Q3 2026 BUY +4.18% +15.34% +13.32% 100.0% Pending
Q2 2026 SELL -1.97% -10.71% -10.01% 98.5% Pending
Q2 2026 BUY +3.82% +14.30% +12.42% 86.4% Pending
Q1 2026 BUY +4.48% +15.79% +17.30% 99.9% +12.13%
Q3 2025 BUY +5.76% +16.11% +13.51% 100.0% +13.92%

Earnings Transcripts

SEC 8-K filings with transcript text

View All
2026
Q3

Q3 2026 Earnings

8-K BUY

Nov 10, 2026 · 100% conf.

AI Prediction BUY

1D

+4.18%

$11.77

Act: +2.48%

5D

+15.34%

$13.03

20D

+13.32%

$12.81

Price: $11.30 Prob +5D: 100% AUC: 1.000
0001728117-26-000116

EX-99.1

2 goss-20261110xexx991xearni.htm

EX-99.1

Document

Exhibit 99.1

Gossamer Bio Announces Third Quarter 2026 Financial Results and Provides Business Update

– New Drug Application for Seralutinib in PAH Submitted to the U.S. FDA in September 2026 –

– Structured Private Placement Provides $25 Million Upfront and Up to $125 Million of Additional Committed Capital Upon FDA Acceptance of the Seralutinib NDA –

– 1-for-80 Reverse Stock Split Completed in September 2026 –

- Cash, Cash Equivalents and Marketable Securities Totaled $51.2 Million as of September 30, 2026 -

SAN DIEGO—(BUSINESS WIRE)— November 10, 2026 — Gossamer Bio, Inc. (Nasdaq: GOSS) (the “Company” or “Gossamer”), a clinical-stage biopharmaceutical company focused on the development and commercialization of seralutinib for the treatment of pulmonary arterial hypertension (PAH) and pulmonary hypertension associated with interstitial lung disease (PH-ILD), today announced its financial results for the third quarter ended September 30, 2026, and provided a business update.

“Submitting our first NDA marks an important milestone for Gossamer in our continued efforts to bring seralutinib to patients living with PAH,” said Faheem Hasnain, Chairman, Co-Founder and Chief Executive Officer of Gossamer Bio. “Furthermore, FDA acceptance of the application in 2026 would, subject to other customary closing conditions, unlock up to approximately $125 million in additional committed capital to support our priorities, including preparations for a potential launch. We remain focused on supporting the FDA’s review and preparing for a potential commercial launch of seralutinib in 2027.”

Seralutinib (GB002): Inhaled PDGFRα/β, CSF1R and c-KIT Inhibitor

New Drug Application Submitted for Seralutinib in PAH

•    Gossamer submitted a New Drug Application (NDA) to the U.S. Food and Drug Administration (FDA) in September 2026 for seralutinib for the treatment of PAH. This is the Company’s first NDA submission.

•    The NDA is supported by the Phase 3 PROSERA Study as one adequate and well-controlled clinical investigation, together with confirmatory evidence from the Phase 2 TORREY Study and additional supportive analyses.

•    The FDA will determine whether to accept the NDA for filing following its initial review.

•    Seralutinib is investigational and has not been approved by any regulatory authority.

Corporate and Business Updates

Reacquisition of Worldwide Rights to Seralutinib from Chiesi

•    In July 2026, Gossamer entered into an agreement with Chiesi Farmaceutici S.p.A. (“Chiesi”) under which Gossamer reacquired worldwide development and commercial rights to seralutinib, terminating their prior collaboration. The agreement provided for a one-time $5 million payment from Chiesi, with no upfront cash payment by Gossamer. Chiesi remains entitled to a capped royalty and certain regulatory and commercial milestone payments.

Structured Private Placement

•    In August 2026, Gossamer announced a structured private placement with total potential gross proceeds of up to approximately $250 million, including approximately $150 million of committed capital across the initial and second closings.

•    The initial closing provided approximately $25 million of gross proceeds.

•    The second closing provides for up to approximately $125 million of additional gross proceeds upon FDA acceptance of the seralutinib NDA in PAH, subject to the applicable milestone occurring in 2026 and other customary closing conditions.

•    Warrants related to FDA approval could provide up to approximately $100 million of additional gross proceeds, contingent upon FDA approval of seralutinib and cash exercise of the warrants.

Reverse Stock Split

•    Gossamer completed a 1-for-80 reverse stock split in September 2026, and split-adjusted trading commenced under the existing Nasdaq symbol “GOSS.” The reverse stock split was effected to regain compliance with the Nasdaq minimum bid price requirement.

Financial Results for the Quarter Ended September 30, 2026

•Cash, Cash Equivalents and Marketable Securities: Cash, cash equivalents and marketable securities totaled $51.2 million as of September 30, 2026, compared to $57.0 million as of June 30, 2026.

•Revenue from contracts with collaborators: For the quarter ended September 30, 2026, revenue from contracts with collaborators was $38.4 million, compared to $13.3 million for the same period in 2025. The increase of $25.1 million is primarily attributable to revenue recognized upon the termination of the Chiesi Collaboration Agreement in July 2026 in connection with Gossamer’s reacquisition of worldwide rights to seralutinib.

•Research and Development (R&D) Expenses: For the quarter ended September 30, 2026, R&D expenses were $18.8 million, compared to $45.5 million for the same period in 2025. The change was primarily driven by a decrease of $15.7 million of costs associated with clinical trials for seralutinib.

•General

2026
Q2

Q2 2026 Earnings

8-K BUY

Aug 13, 2026 · 86% conf.

AI Prediction BUY

1D

+3.82%

$0.20

Act: +5.18%

5D

+14.30%

$0.22

20D

+12.42%

$0.22

Price: $0.20 Prob +5D: 93% AUC: 1.000
0001728117-26-000073

Transcript text not available. View on SEC.gov →

2026
Q2

Q2 2026 Earnings

8-K BUY

Jul 27, 2026 · 86% conf.

AI Prediction BUY

1D

+3.82%

$0.20

Act: +5.18%

5D

+14.30%

$0.22

20D

+12.42%

$0.22

Price: $0.20 Prob +5D: 93% AUC: 1.000
0001728117-26-000064

SEC.gov | Request Rate Threshold Exceeded

U.S. Securities and Exchange Commission

You’ve Exceeded the SEC’s Traffic Limit

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Reference ID: 0.e618d017.1785589247.2f8f196e

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2026
Q1

Q1 2026 Earnings

8-K BUY

May 18, 2026 · 100% conf.

AI Prediction BUY

1D

+4.48%

$0.20

Act: +1.38%

5D

+15.79%

$0.23

Act: +12.13%

20D

+17.30%

$0.23

Act: -14.53%

Price: $0.20 Prob +5D: 100% AUC: 1.000
0001728117-26-000036

SEC.gov | Request Rate Threshold Exceeded

U.S. Securities and Exchange Commission

You’ve Exceeded the SEC’s Traffic Limit

Your request rate has exceeded the SEC’s maximum allowable requests per second. Your access to SEC.gov will be limited for 10 minutes.

Current guidelines limit each user to a total of no more than 10 requests per second, regardless of the number of machines used to submit requests. To ensure that SEC.gov remains available to all users, we reserve the right to block IP addresses that submit excessive requests.

The block will be lifted automatically by waiting 10 minutes. Continuing to exceed the SEC’s maximum allowable request rate during the time-out period will extend the duration of the time-out period. To ensure fair access for all users, please reduce the rate of your requests and visit SEC.gov again after the 10 minute time-out period has passed.

For best practices on efficiently downloading information from SEC.gov, including the latest EDGAR filings, visit sec.gov/developer. You can also sign up for email updates on the SEC open data program, including best practices that make it more efficient to download data, and SEC.gov enhancements that may impact scripted downloading processes. For more information, contact opendata@sec.gov.

For more information, please see the SEC’s Web Site Privacy and Security Policy. Thank you for your interest in the U.S. Securities and Exchange Commission.

Reference ID: 0.c706d217.1784380849.d60049fa

More Information

Internet Security Policy

By using this site, you are agreeing to security monitoring and auditing. For security purposes, and to ensure that the public service remains available to users, this government computer system employs programs to monitor network traffic to identify unauthorized attempts to upload or change information or to otherwise cause damage, including attempts to deny service to users.

Unauthorized attempts to upload information and/or change information on any portion of this site are strictly prohibited and are subject to prosecution under the Computer Fraud and Abuse Act of 1986 and the National Information Infrastructure Protection Act of 1996 (see Title 18 U.S.C. §§ 1001 and 1030).

To ensure our website performs well for all users, the SEC monitors the frequency of requests for SEC.gov content to ensure automated searches do not impact the ability of others to access SEC.gov content. We reserve the right to block IP addresses that submit excessive requests. Current guidelines limit users to a total of no more than 10 requests per second, regardless of the number of machines used to submit requests.

If a user or application submits more than 10 requests per second, further requests from the IP address(es) may be limited for a brief period. Once the rate of requests has dropped below the threshold for 10 minutes, the user may resume accessing content on SEC.gov. This SEC practice is designed to limit excessive automated searches on SEC.gov and is not intended or expected to impact individuals browsing the SEC.gov website.

Note that this policy may change as the SEC manages SEC.gov to ensure that the website performs efficiently and remains available to all users.

Note: We do not offer technical support for developing or debugging scripted downloading processes.

2025
Q4

Q4 2025 Earnings

8-K

Mar 17, 2026

0001728117-26-000018

SEC.gov | Request Rate Threshold Exceeded

U.S. Securities and Exchange Commission

You’ve Exceeded the SEC’s Traffic Limit

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For best practices on efficiently downloading information from SEC.gov, including the latest EDGAR filings, visit sec.gov/developer. You can also sign up for email updates on the SEC open data program, including best practices that make it more efficient to download data, and SEC.gov enhancements that may impact scripted downloading processes. For more information, contact opendata@sec.gov.

For more information, please see the SEC’s Web Site Privacy and Security Policy. Thank you for your interest in the U.S. Securities and Exchange Commission.

Reference ID: 0.c706d217.1784380851.d60064e2

More Information

Internet Security Policy

By using this site, you are agreeing to security monitoring and auditing. For security purposes, and to ensure that the public service remains available to users, this government computer system employs programs to monitor network traffic to identify unauthorized attempts to upload or change information or to otherwise cause damage, including attempts to deny service to users.

Unauthorized attempts to upload information and/or change information on any portion of this site are strictly prohibited and are subject to prosecution under the Computer Fraud and Abuse Act of 1986 and the National Information Infrastructure Protection Act of 1996 (see Title 18 U.S.C. §§ 1001 and 1030).

To ensure our website performs well for all users, the SEC monitors the frequency of requests for SEC.gov content to ensure automated searches do not impact the ability of others to access SEC.gov content. We reserve the right to block IP addresses that submit excessive requests. Current guidelines limit users to a total of no more than 10 requests per second, regardless of the number of machines used to submit requests.

If a user or application submits more than 10 requests per second, further requests from the IP address(es) may be limited for a brief period. Once the rate of requests has dropped below the threshold for 10 minutes, the user may resume accessing content on SEC.gov. This SEC practice is designed to limit excessive automated searches on SEC.gov and is not intended or expected to impact individuals browsing the SEC.gov website.

Note that this policy may change as the SEC manages SEC.gov to ensure that the website performs efficiently and remains available to all users.

Note: We do not offer technical support for developing or debugging scripted downloading processes.

2025
Q3

Q3 2025 Earnings

8-K BUY

Nov 5, 2025 · 100% conf.

AI Prediction BUY

1D

+5.76%

$2.51

Act: -3.16%

5D

+16.11%

$2.75

Act: +13.92%

20D

+13.51%

$2.69

Act: +40.08%

Price: $2.37 Prob +5D: 100% AUC: 1.000
0001728117-25-000082

goss-202511050001728117FALSE00017281172025-11-052025-11-05

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 5, 2025

GOSSAMER BIO, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware001-3879647-5461709 (State or Other Jurisdiction of Incorporation)(Commission File Number)(IRS Employer Identification No.)

3115 Merryfield Row, Suite 120 San Diego, California, 92121

(Address of Principal Executive Offices) (Zip Code) (858) 684-1300 (Registrant’s Telephone Number, Including Area Code) N/A (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instructions A.2. below):

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.0001 par value per share GOSS Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 2.02 Results of Operations and Financial Condition. On November 5, 2025, Gossamer Bio, Inc. (the “Company”) issued a press release reporting its financial results for the quarter ended September 30, 2025. The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K. In accordance with General Instruction B.2 of Form 8-K, the information contained or incorporated herein, including the press release attached as Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such filing to this Current Report on Form 8-K. Item 9.01 Financial Statements and Exhibits. (d) Exhibits.

Exhibit Number Description 99.1 Press Release dated November 5, 2025

101  Cover Page Interactive Data File (embedded within the Inline XBRL document)

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

GOSSAMER BIO, INC.

Date: November 5, 2025 By:/s/ Bryan Giraudo Bryan Giraudo Chief Financial Officer and Chief Operating Officer

2

2025
Q2

Q2 2025 Earnings

8-K

Aug 5, 2025

0001728117-25-000069

goss-202508050001728117FALSE00017281172025-08-052025-08-05

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 5, 2025

GOSSAMER BIO, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware001-3879647-5461709 (State or Other Jurisdiction of Incorporation)(Commission File Number)(IRS Employer Identification No.)

3115 Merryfield Row, Suite 120 San Diego, California, 92121

(Address of Principal Executive Offices) (Zip Code) (858) 684-1300 (Registrant’s Telephone Number, Including Area Code) N/A (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instructions A.2. below):

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.0001 par value per share GOSS Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 2.02 Results of Operations and Financial Condition. On August 5, 2025, Gossamer Bio, Inc. (the “Company”) issued a press release reporting its financial results for the quarter ended June 30, 2025. The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K. In accordance with General Instruction B.2 of Form 8-K, the information contained or incorporated herein, including the press release attached as Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such filing to this Current Report on Form 8-K. Item 9.01 Financial Statements and Exhibits. (d) Exhibits.

Exhibit Number Description 99.1 Press Release dated August 5, 2025

101  Cover Page Interactive Data File (embedded within the Inline XBRL document)

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

GOSSAMER BIO, INC.

Date: August 5, 2025 By:/s/ Bryan Giraudo Bryan Giraudo Chief Financial Officer and Chief Operating Officer

2

2025
Q1

Q1 2025 Earnings

8-K

May 15, 2025

0001728117-25-000037

goss-202505150001728117FALSE00017281172025-05-152025-05-15

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 15, 2025

GOSSAMER BIO, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware001-3879647-5461709 (State or Other Jurisdiction of Incorporation)(Commission File Number)(IRS Employer Identification No.)

3115 Merryfield Row, Suite 120 San Diego, California, 92121

(Address of Principal Executive Offices) (Zip Code) (858) 684-1300 (Registrant’s Telephone Number, Including Area Code) N/A (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instructions A.2. below):

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.0001 par value per share GOSS Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 2.02 Results of Operations and Financial Condition. On May 15, 2025, Gossamer Bio, Inc. (the “Company”) issued a press release reporting its financial results for the quarter ended March 31, 2025. The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K. In accordance with General Instruction B.2 of Form 8-K, the information contained or incorporated herein, including the press release attached as Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such filing to this Current Report on Form 8-K. Item 9.01 Financial Statements and Exhibits. (d) Exhibits.

Exhibit Number Description 99.1 Press Release dated May 15, 2025

101  Cover Page Interactive Data File (embedded within the Inline XBRL document)

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

GOSSAMER BIO, INC.

Date: May 15, 2025 By:/s/ Bryan Giraudo Bryan Giraudo Chief Financial Officer and Chief Operating Officer

2

2024
Q4

Q4 2024 Earnings

8-K

Mar 13, 2025

0001728117-25-000022

goss-202503130001728117FALSE00017281172024-03-132024-03-13

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 13, 2025

GOSSAMER BIO, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware001-3879647-5461709 (State or Other Jurisdiction of Incorporation)(Commission File Number)(IRS Employer Identification No.)

3115 Merryfield Row, Suite 120 San Diego, California, 92121

(Address of Principal Executive Offices) (Zip Code) (858) 684-1300 (Registrant’s Telephone Number, Including Area Code) N/A (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instructions A.2. below):

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.0001 par value per share GOSS Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 2.02 Results of Operations and Financial Condition. On March 13, 2025, Gossamer Bio, Inc. (the “Company”) issued a press release reporting its financial results for the quarter and fiscal year ended December 31, 2024. The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K. In accordance with General Instruction B.2 of Form 8-K, the information contained or incorporated herein, including the press release attached as Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such filing to this Current Report on Form 8-K. Item 9.01 Financial Statements and Exhibits. (d) Exhibits.

Exhibit Number Description 99.1 Press Release dated March 13, 2025

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

GOSSAMER BIO, INC.

Date: March 13, 2025 By:/s/ Bryan Giraudo Bryan Giraudo Chief Operating Officer and Chief Financial Officer

2

2024
Q3

Q3 2024 Earnings

8-K

Nov 7, 2024

0001728117-24-000093

goss-202411070001728117FALSE00017281172024-11-072024-11-07

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 7, 2024

GOSSAMER BIO, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware001-3879647-5461709 (State or Other Jurisdiction of Incorporation)(Commission File Number)(IRS Employer Identification No.)

3115 Merryfield Row, Suite 120 San Diego, California, 92121

(Address of Principal Executive Offices) (Zip Code) (858) 684-1300 (Registrant’s Telephone Number, Including Area Code) N/A (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instructions A.2. below):

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.0001 par value per share GOSS Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 2.02 Results of Operations and Financial Condition. On November 7, 2024, Gossamer Bio, Inc. (the “Company”) issued a press release reporting its financial results for the quarter ended September 30, 2024. The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K. In accordance with General Instruction B.2 of Form 8-K, the information contained or incorporated herein, including the press release attached as Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such filing to this Current Report on Form 8-K. Item 9.01 Financial Statements and Exhibits. (d) Exhibits.

Exhibit Number Description 99.1 Press Release dated November 7, 2024

101  Cover Page Interactive Data File (embedded within the Inline XBRL document)

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

GOSSAMER BIO, INC.

Date: November 7, 2024 By:/s/ Bryan Giraudo Bryan Giraudo Chief Operating Officer and Chief Financial Officer

2

2024
Q2

Q2 2024 Earnings

8-K

Aug 12, 2024

0001728117-24-000086

goss-202408120001728117FALSE00017281172024-08-122024-08-12

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 12, 2024

GOSSAMER BIO, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware001-3879647-5461709 (State or Other Jurisdiction of Incorporation)(Commission File Number)(IRS Employer Identification No.)

3013 Science Park Road San Diego, California, 92121

(Address of Principal Executive Offices) (Zip Code) (858) 684-1300 (Registrant’s Telephone Number, Including Area Code) N/A (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instructions A.2. below):

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.0001 par value per share GOSS Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 2.02 Results of Operations and Financial Condition. On August 12, 2024, Gossamer Bio, Inc. (the “Company”) issued a press release reporting its financial results for the quarter ended June 30, 2024. The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K. In accordance with General Instruction B.2 of Form 8-K, the information contained or incorporated herein, including the press release attached as Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such filing to this Current Report on Form 8-K. Item 9.01 Financial Statements and Exhibits. (d) Exhibits.

Exhibit Number Description 99.1 Press Release dated August 12, 2024

101  Cover Page Interactive Data File (embedded within the Inline XBRL document)

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

GOSSAMER BIO, INC.

Date: August 12, 2024 By:/s/ Bryan Giraudo Bryan Giraudo Chief Operating Officer and Chief Financial Officer

2

2024
Q1

Q1 2024 Earnings

8-K

May 7, 2024

0001728117-24-000057

goss-202405070001728117FALSE00017281172024-05-072024-05-07

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 7, 2024

GOSSAMER BIO, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware001-3879647-5461709 (State or Other Jurisdiction of Incorporation)(Commission File Number)(IRS Employer Identification No.)

3013 Science Park Road San Diego, California, 92121

(Address of Principal Executive Offices) (Zip Code) (858) 684-1300 (Registrant’s Telephone Number, Including Area Code) N/A (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instructions A.2. below):

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.0001 par value per share GOSS Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 2.02 Results of Operations and Financial Condition. On May 7, 2024, Gossamer Bio, Inc. (the “Company”) issued a press release reporting its financial results for the quarter ended March 31, 2024. The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K. In accordance with General Instruction B.2 of Form 8-K, the information contained or incorporated herein, including the press release attached as Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such filing to this Current Report on Form 8-K. Item 9.01 Financial Statements and Exhibits. (d) Exhibits.

Exhibit Number Description 99.1 Press Release dated May 7, 2024

101  Cover Page Interactive Data File (embedded within the Inline XBRL document)

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

GOSSAMER BIO, INC.

Date: May 7, 2024 By:/s/ Bryan Giraudo Bryan Giraudo Chief Operating Officer and Chief Financial Officer

2

2023
Q4

Q4 2023 Earnings

8-K

Mar 5, 2024

0001728117-24-000018

goss-202403050001728117FALSE00017281172024-03-072024-03-07

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 5, 2024

GOSSAMER BIO, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware001-3879647-5461709 (State or Other Jurisdiction of Incorporation)(Commission File Number)(IRS Employer Identification No.)

3013 Science Park Road San Diego, California, 92121

(Address of Principal Executive Offices) (Zip Code) (858) 684-1300 (Registrant’s Telephone Number, Including Area Code) N/A (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instructions A.2. below):

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.0001 par value per share GOSS Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 2.02 Results of Operations and Financial Condition. On March 5, 2024, Gossamer Bio, Inc. (the “Company”) issued a press release reporting its financial results for the quarter and fiscal year ended December 31, 2023. The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K. In accordance with General Instruction B.2 of Form 8-K, the information contained or incorporated herein, including the press release attached as Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such filing to this Current Report on Form 8-K. Item 9.01 Financial Statements and Exhibits. (d) Exhibits.

Exhibit Number Description 99.1 Press Release dated March 5, 2024

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

GOSSAMER BIO, INC.

Date: March 5, 2024 By:/s/ Bryan Giraudo Bryan Giraudo Chief Operating Officer and Chief Financial Officer

2

2023
Q3

Q3 2023 Earnings

8-K

Nov 9, 2023

0001728117-23-000133

goss-202311090001728117FALSE00017281172023-11-092023-11-09

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 9, 2023

GOSSAMER BIO, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware001-3879647-5461709 (State or Other Jurisdiction of Incorporation)(Commission File Number)(IRS Employer Identification No.)

3013 Science Park Road San Diego, California, 92121

(Address of Principal Executive Offices) (Zip Code) (858) 684-1300 (Registrant’s Telephone Number, Including Area Code) N/A (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instructions A.2. below):

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.0001 par value per share GOSS Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 2.02 Results of Operations and Financial Condition. On November 9, 2023, Gossamer Bio, Inc. (the “Company”) issued a press release reporting its financial results for the quarter ended September 30, 2023. The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K. In accordance with General Instruction B.2 of Form 8-K, the information contained or incorporated herein, including the press release attached as Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such filing to this Current Report on Form 8-K. Item 9.01 Financial Statements and Exhibits. (d) Exhibits.

Exhibit Number Description 99.1 Press Release dated November 9, 2023

104  Cover Page Interactive Data File (embedded within the Inline XBRL document)

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

GOSSAMER BIO, INC.

Date: November 9, 2023 By:/s/ Bryan Giraudo Bryan Giraudo Chief Operating Officer and Chief Financial Officer

2

2023
Q2

Q2 2023 Earnings

8-K

Aug 8, 2023

0001728117-23-000107

goss-202308080001728117FALSE00017281172023-08-082023-08-08

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 8, 2023

GOSSAMER BIO, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware001-3879647-5461709 (State or Other Jurisdiction of Incorporation)(Commission File Number)(IRS Employer Identification No.)

3013 Science Park Road San Diego, California, 92121

(Address of Principal Executive Offices) (Zip Code) (858) 684-1300 (Registrant’s Telephone Number, Including Area Code) N/A (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instructions A.2. below):

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.0001 par value per share GOSS Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 2.02 Results of Operations and Financial Condition. On August 8, 2023, Gossamer Bio, Inc. (the “Company”) issued a press release reporting its financial results for the quarter ended June 30, 2023. The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K. In accordance with General Instruction B.2 of Form 8-K, the information contained or incorporated herein, including the press release attached as Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such filing to this Current Report on Form 8-K. Item 9.01 Financial Statements and Exhibits. (d) Exhibits.

Exhibit Number Description 99.1 Press Release dated August 8, 2023

104  Cover Page Interactive Data File (embedded within the Inline XBRL document)

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

GOSSAMER BIO, INC.

Date: August 8, 2023 By:/s/ Bryan Giraudo Bryan Giraudo Chief Operating Officer and Chief Financial Officer

2

2023
Q1

Q1 2023 Earnings

8-K

May 9, 2023

0001728117-23-000050

goss-202305090001728117FALSE00017281172023-05-092023-05-09

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 9, 2023

GOSSAMER BIO, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware001-3879647-5461709 (State or Other Jurisdiction of Incorporation)(Commission File Number)(IRS Employer Identification No.)

3013 Science Park Road San Diego, California, 92121

(Address of Principal Executive Offices) (Zip Code) (858) 684-1300 (Registrant’s Telephone Number, Including Area Code) N/A (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instructions A.2. below):

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.0001 par value per share GOSS Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 2.02 Results of Operations and Financial Condition. On May 9, 2023, Gossamer Bio, Inc. (the “Company”) issued a press release reporting its financial results for the quarter ended March 31, 2023. The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K. In accordance with General Instruction B.2 of Form 8-K, the information contained or incorporated herein, including the press release attached as Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such filing to this Current Report on Form 8-K. Item 9.01 Financial Statements and Exhibits. (d) Exhibits.

Exhibit Number Description 99.1 Press Release dated May 9, 2023

104  Cover Page Interactive Data File (embedded within the Inline XBRL document)

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

GOSSAMER BIO, INC.

Date: May 9, 2023 By:/s/ Bryan Giraudo Bryan Giraudo Chief Operating Officer and Chief Financial Officer

2

2022
Q4

Q4 2022 Earnings

8-K

Mar 17, 2023

0001728117-23-000009

goss-202303170001728117FALSE00017281172023-03-172023-03-17

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 17, 2023

GOSSAMER BIO, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware001-3879647-5461709 (State or Other Jurisdiction of Incorporation)(Commission File Number)(IRS Employer Identification No.)

3013 Science Park Road San Diego, California, 92121

(Address of Principal Executive Offices) (Zip Code) (858) 684-1300 (Registrant’s Telephone Number, Including Area Code) N/A (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instructions A.2. below):

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.0001 par value per share GOSS Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 2.02 Results of Operations and Financial Condition. On March 17, 2023, Gossamer Bio, Inc. (the “Company”) issued a press release reporting its financial results for the quarter and fiscal year ended December 31, 2022. The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K. In accordance with General Instruction B.2 of Form 8-K, the information contained or incorporated herein, including the press release attached as Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such filing to this Current Report on Form 8-K. Item 9.01 Financial Statements and Exhibits. (d) Exhibits.

Exhibit Number Description 99.1 Press Release dated March 17, 2023

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

GOSSAMER BIO, INC.

Date: March 17, 2023 By:/s/ Bryan Giraudo Bryan Giraudo Chief Operating Officer and Chief Financial Officer

2

2022
Q3

Q3 2022 Earnings

8-K

Nov 3, 2022

0001728117-22-000099

goss-202211030001728117FALSE00017281172022-11-032022-11-03

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 3, 2022

GOSSAMER BIO, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware001-3879647-5461709 (State or Other Jurisdiction of Incorporation)(Commission File Number)(IRS Employer Identification No.)

3013 Science Park Road San Diego, California, 92121

(Address of Principal Executive Offices) (Zip Code) (858) 684-1300 (Registrant’s Telephone Number, Including Area Code) N/A (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instructions A.2. below):

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.0001 par value per share GOSS Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 2.02 Results of Operations and Financial Condition. On November 3, 2022, Gossamer Bio, Inc. (the “Company”) issued a press release reporting its financial results for the quarter ended September 30, 2022. The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K. In accordance with General Instruction B.2 of Form 8-K, the information contained or incorporated herein, including the press release attached as Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such filing to this Current Report on Form 8-K. Item 9.01 Financial Statements and Exhibits. (d) Exhibits.

Exhibit Number Description 99.1 Press Release dated November 3, 2022

104  Cover Page Interactive Data File (embedded within the Inline XBRL document)

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

GOSSAMER BIO, INC.

Date: November 3, 2022 By:/s/ Bryan Giraudo Bryan Giraudo Chief Operating Officer and Chief Financial Officer

2

2022
Q2

Q2 2022 Earnings

8-K

Aug 9, 2022

0001728117-22-000084

goss-202208090001728117FALSE00017281172022-08-092022-08-09

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 9, 2022

GOSSAMER BIO, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware001-3879647-5461709 (State or Other Jurisdiction of Incorporation)(Commission File Number)(IRS Employer Identification No.)

3013 Science Park Road San Diego, California, 92121

(Address of Principal Executive Offices) (Zip Code) (858) 684-1300 (Registrant’s Telephone Number, Including Area Code) N/A (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instructions A.2. below):

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.0001 par value per share GOSS Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 2.02 Results of Operations and Financial Condition. On August 9, 2022, Gossamer Bio, Inc. (the “Company”) issued a press release reporting its financial results for the quarter ended June 30, 2022. The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K. In accordance with General Instruction B.2 of Form 8-K, the information contained or incorporated herein, including the press release attached as Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such filing to this Current Report on Form 8-K. Item 9.01 Financial Statements and Exhibits. (d) Exhibits.

Exhibit Number Description 99.1 Press Release dated August 9, 2022

104  Cover Page Interactive Data File (embedded within the Inline XBRL document)

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

GOSSAMER BIO, INC.

Date: August 9, 2022 By:/s/ Bryan Giraudo Bryan Giraudo Chief Operating Officer and Chief Financial Officer

2

2022
Q1

Q1 2022 Earnings

8-K

May 10, 2022

0001728117-22-000046

8-K 1 goss-20220510x8k.htm 8-K

Document

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 10, 2022

GOSSAMER BIO, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware001-3879647-5461709 (State or Other Jurisdictionof Incorporation)(Commission File Number)(IRS EmployerIdentification No.)

3013 Science Park Road San Diego, California, 92121

(Address of Principal Executive Offices) (Zip Code) (858) 684-1300 (Registrant’s Telephone Number, Including Area Code) N/A (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instructions A.2. below):

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class TradingSymbol(s) Name of each exchange on which registered Common Stock, $0.0001 par value per share GOSS Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 2.02 Results of Operations and Financial Condition. On May 10, 2022, Gossamer Bio, Inc. (the “Company”) issued a press release reporting its financial results for the quarter ended March 31, 2022. The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K. In accordance with General Instruction B.2 of Form 8-K, the information contained or incorporated herein, including the press release attached as Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such filing to this Current Report on Form 8-K. Item 9.01 Financial Statements and Exhibits. (d) Exhibits.

ExhibitNumber Description 99.1 Press Release dated May 10, 2022

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

GOSSAMER BIO, INC.

Date: May 10, 2022 By:/s/ Bryan Giraudo Bryan Giraudo Chief Operating Officer and Chief Financial Officer

2

About Gossamer Bio Inc. (GOSS) Earnings

This page provides Gossamer Bio Inc. (GOSS) earnings call transcripts from SEC 8-K filings along with AI-powered predictions for post-earnings price movements. Our machine learning models analyze historical earnings data, pre-earnings price patterns, volume changes, and volatility to predict 1-day, 5-day, and 20-day returns after each earnings release.

Earnings transcripts are sourced directly from SEC EDGAR filings. Predictions are generated using gradient boosting models trained on GOSS's historical earnings reactions. All predicted returns are shown as percentages, and predicted prices are calculated from the closing price at the time of prediction. Past performance does not guarantee future results.

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