Zenas BioPharma, Inc. SEC filings ZBIO
Zenas BioPharma, Inc. has 193 filings in SEC EDGAR's recent list, going back to Nov 15, 2022. Its latest annual report, Form ARS, was filed on Mar 16, 2026 for the period ended Dec 31, 2025. The latest quarterly report (Form 10-Q) was filed on Nov 5, 2026, covering the quarter ended Sep 30, 2026. The most recent current report (Form 8-K) was filed on Nov 5, 2026 (results of operations). The company's fiscal year ends on December 31.
| Form | Description | Filed | Period |
|---|---|---|---|
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Nov 5, 2026 | — |
| 10-Q | Quarterly report | Nov 5, 2026 | Sep 30, 2026 |
| 8-K |
Current report
Results of operations
|
Nov 5, 2026 | Nov 5, 2026 |
| SCHEDULE 13G | Ownership over 5% (passive) | Oct 27, 2026 | — |
| 8-K |
Current report
Regulation FD disclosure
|
Oct 13, 2026 | Oct 12, 2026 |
| S-3ASR | Automatic shelf registration | Sep 11, 2026 | — |
| S-8 | Employee stock plan registration | Sep 11, 2026 | — |
| SCHEDULE 13G | Ownership over 5% (passive) | Sep 8, 2026 | — |
| 3 | Initial insider ownership | Sep 8, 2026 | Aug 26, 2026 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Sep 8, 2026 | — |
| 4 | Insider transaction | Sep 2, 2026 | Sep 1, 2026 |
| 3 | Initial insider ownership | Sep 2, 2026 | Sep 1, 2026 |
| SCHEDULE 13D/A | Amended ownership over 5% (active) | Aug 19, 2026 | — |
| 144 | Notice of proposed sale | Aug 19, 2026 | — |
| SCHEDULE 13D/A | Amended ownership over 5% (active) | Aug 17, 2026 | — |
| 10-Q | Quarterly report | Aug 13, 2026 | Jun 30, 2026 |
| 8-K |
Current report
Results of operations, Officer or director change
|
Aug 13, 2026 | Aug 12, 2026 |
| 4 | Insider transaction | Jun 17, 2026 | Jun 15, 2026 |
| 4 | Insider transaction | Jun 17, 2026 | Jun 15, 2026 |
| 4 | Insider transaction | Jun 17, 2026 | Jun 15, 2026 |
| 4 | Insider transaction | Jun 17, 2026 | Jun 15, 2026 |
| 4 | Insider transaction | Jun 17, 2026 | Jun 15, 2026 |
| 4 | Insider transaction | Jun 17, 2026 | Jun 15, 2026 |
| 4 | Insider transaction | Jun 17, 2026 | Jun 15, 2026 |
| 4 | Insider transaction | Jun 17, 2026 | Jun 15, 2026 |
| 4 | Insider transaction | Jun 17, 2026 | Jun 15, 2026 |
| 4 | Insider transaction | Jun 17, 2026 | Jun 15, 2026 |
| 4 | Insider transaction | May 18, 2026 | May 18, 2026 |
| 10-Q | Quarterly report | May 13, 2026 | Mar 31, 2026 |
| 8-K |
Current report
Results of operations, Officer or director change, Shareholder vote results
|
May 13, 2026 | May 11, 2026 |
| SCHEDULE 13D | Ownership over 5% (active) | May 5, 2026 | — |
| 4 | Insider transaction | Apr 29, 2026 | Apr 28, 2026 |
| SCHEDULE 13D/A | Amended ownership over 5% (active) | Apr 2, 2026 | — |
| 4 | Insider transaction | Apr 2, 2026 | Mar 31, 2026 |
| 4 | Insider transaction | Apr 1, 2026 | Mar 31, 2026 |
| 4 | Insider transaction | Mar 31, 2026 | Mar 30, 2026 |
| 4 | Insider transaction | Mar 31, 2026 | Mar 31, 2026 |
| 8-K |
Current report
Material agreement, New debt, Other events
|
Mar 31, 2026 | Mar 26, 2026 |
| 424B5 | Prospectus supplement | Mar 30, 2026 | — |
| 424B5 | Prospectus supplement | Mar 30, 2026 | — |
| FWP | Free writing prospectus | Mar 27, 2026 | — |
| FWP | Free writing prospectus | Mar 27, 2026 | — |
| 424B5 | Prospectus supplement | Mar 26, 2026 | — |
| 424B5 | Prospectus supplement | Mar 26, 2026 | — |
| FWP | Free writing prospectus | Mar 26, 2026 | — |
| DEFA14A | Additional proxy material | Mar 16, 2026 | — |
| ARS | Annual report to shareholders | Mar 16, 2026 | Dec 31, 2025 |
| DEF 14A | Proxy statement | Mar 16, 2026 | May 11, 2026 |
| S-8 | Employee stock plan registration | Mar 16, 2026 | — |
| 10-K | Annual report | Mar 16, 2026 | Dec 31, 2025 |
| 8-K |
Current report
Results of operations
|
Mar 16, 2026 | Mar 16, 2026 |
| 4 | Insider transaction | Feb 13, 2026 | Feb 11, 2026 |
| 4 | Insider transaction | Feb 13, 2026 | Feb 12, 2026 |
| 8-K |
Current report
Officer or director change
|
Feb 13, 2026 | Feb 10, 2026 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Feb 5, 2026 | — |
| 4 | Insider transaction | Feb 3, 2026 | Feb 2, 2026 |
| 424B7 | Filing | Jan 28, 2026 | — |
| SCHEDULE 13D | Ownership over 5% (active) | Jan 14, 2026 | — |
| 4 | Insider transaction | Jan 9, 2026 | Jan 7, 2026 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure, Other events
|
Jan 5, 2026 | Jan 5, 2026 |
| S-8 | Employee stock plan registration | Dec 19, 2025 | — |
| 8-K |
Current report
Officer or director change
|
Dec 15, 2025 | Dec 10, 2025 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Nov 14, 2025 | — |
| 10-Q | Quarterly report | Nov 12, 2025 | Sep 30, 2025 |
| 8-K |
Current report
Results of operations
|
Nov 12, 2025 | Nov 12, 2025 |
| 8-K |
Current report
Regulation FD disclosure, Other events
|
Oct 27, 2025 | Oct 27, 2025 |
| S-3ASR | Automatic shelf registration | Oct 21, 2025 | — |
| 3 | Initial insider ownership | Oct 15, 2025 | Oct 7, 2025 |
| SCHEDULE 13G | Ownership over 5% (passive) | Oct 15, 2025 | — |
| SCHEDULE 13D/A | Amended ownership over 5% (active) | Oct 14, 2025 | — |
| SCHEDULE 13D/A | Amended ownership over 5% (active) | Oct 14, 2025 | — |
| 4 | Insider transaction | Oct 14, 2025 | Oct 9, 2025 |
| 4 | Insider transaction | Oct 14, 2025 | Oct 9, 2025 |
| SCHEDULE 13D/A | Amended ownership over 5% (active) | Oct 14, 2025 | — |
| 4 | Insider transaction | Oct 14, 2025 | Oct 9, 2025 |
| 4 | Insider transaction | Oct 9, 2025 | Oct 7, 2025 |
| SCHEDULE 13D/A | Amended ownership over 5% (active) | Oct 9, 2025 | — |
| 4 | Insider transaction | Oct 9, 2025 | Oct 7, 2025 |
| 4 | Insider transaction | Oct 9, 2025 | Sep 13, 2024 |
| S-3ASR | Automatic shelf registration | Oct 8, 2025 | — |
| 8-K |
Current report
Material agreement, Results of operations, Unregistered share sale, Regulation FD disclosure, Other events
|
Oct 8, 2025 | Oct 7, 2025 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Sep 8, 2025 | — |
| 8-K |
Current report
Material agreement, Acquisition or sale of assets, New debt, Regulation FD disclosure
|
Sep 2, 2025 | Sep 2, 2025 |
| S-8 | Employee stock plan registration | Aug 12, 2025 | — |
| 10-Q | Quarterly report | Aug 12, 2025 | Jun 30, 2025 |
| 8-K |
Current report
Results of operations
|
Aug 12, 2025 | Aug 12, 2025 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Aug 6, 2025 | — |
| 4 | Insider transaction | Jun 12, 2025 | Jun 10, 2025 |
| 4 | Insider transaction | Jun 12, 2025 | Jun 10, 2025 |
| 4 | Insider transaction | Jun 12, 2025 | Jun 10, 2025 |
| 4 | Insider transaction | Jun 12, 2025 | Jun 10, 2025 |
| 4 | Insider transaction | Jun 12, 2025 | Jun 10, 2025 |
| 4 | Insider transaction | Jun 12, 2025 | Jun 10, 2025 |
| 4 | Insider transaction | Jun 12, 2025 | Jun 10, 2025 |
| 4 | Insider transaction | Jun 12, 2025 | Jun 10, 2025 |
| 4 | Insider transaction | Jun 12, 2025 | Jun 10, 2025 |
| 4 | Insider transaction | Jun 12, 2025 | Jun 10, 2025 |
| 4 | Insider transaction | Jun 12, 2025 | Jun 10, 2025 |
| 8-K |
Current report
Officer or director change, Shareholder vote results
|
Jun 12, 2025 | Jun 10, 2025 |
| SCHEDULE 13D | Ownership over 5% (active) | Jun 6, 2025 | — |
| 8-K |
Current report
Regulation FD disclosure
|
Jun 4, 2025 | Jun 4, 2025 |
| 10-Q | Quarterly report | May 15, 2025 | Mar 31, 2025 |
| 8-K |
Current report
Results of operations
|
May 15, 2025 | May 15, 2025 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | May 12, 2025 | — |
| 4/A | Ownership document | Apr 28, 2025 | Feb 7, 2025 |
| ARS | Annual report to shareholders | Apr 28, 2025 | Dec 31, 2024 |
| DEFA14A | Additional proxy material | Apr 28, 2025 | — |
| DEF 14A | Proxy statement | Apr 28, 2025 | Jun 10, 2025 |
| 4 | Insider transaction | Apr 17, 2025 | Apr 15, 2025 |
| SCHEDULE 13G | Ownership over 5% (passive) | Apr 1, 2025 | — |
| 3 | Initial insider ownership | Mar 21, 2025 | Mar 17, 2025 |
| S-8 | Employee stock plan registration | Mar 11, 2025 | — |
| 10-K | Annual report | Mar 11, 2025 | Dec 31, 2024 |
| 4 | Insider transaction | Feb 19, 2025 | Feb 18, 2025 |
| 4 | Insider transaction | Feb 11, 2025 | Feb 7, 2025 |
| 8-K |
Current report
Results of operations
|
Feb 5, 2025 | Feb 5, 2025 |
| 4 | Insider transaction | Dec 18, 2024 | Dec 16, 2024 |
| 4 | Insider transaction | Dec 18, 2024 | Dec 16, 2024 |
| 4 | Insider transaction | Dec 4, 2024 | Dec 3, 2024 |
| 8-K |
Current report
Regulation FD disclosure
|
Dec 2, 2024 | Dec 2, 2024 |
| 4 | Insider transaction | Nov 20, 2024 | Nov 18, 2024 |
| SC 13G | Ownership over 5% (passive) | Nov 12, 2024 | — |
| 10-Q | Quarterly report | Nov 12, 2024 | Sep 30, 2024 |
| 8-K |
Current report
Results of operations
|
Nov 12, 2024 | Nov 12, 2024 |
| SC 13G | Ownership over 5% (passive) | Oct 21, 2024 | — |
| SC 13G | Ownership over 5% (passive) | Sep 25, 2024 | — |
| SC 13D | Ownership over 5% (active) | Sep 23, 2024 | — |
| SC 13D | Ownership over 5% (active) | Sep 23, 2024 | — |
| SC 13D | Ownership over 5% (active) | Sep 23, 2024 | — |
| 4 | Insider transaction | Sep 20, 2024 | Sep 18, 2024 |
| 4 | Insider transaction | Sep 18, 2024 | Sep 16, 2024 |
| 4 | Insider transaction | Sep 18, 2024 | Sep 16, 2024 |
| 4/A | Ownership document | Sep 17, 2024 | Sep 12, 2024 |
| 4/A | Ownership document | Sep 17, 2024 | Sep 12, 2024 |
| 4 | Insider transaction | Sep 17, 2024 | Sep 13, 2024 |
| 4 | Insider transaction | Sep 16, 2024 | Sep 12, 2024 |
| 4 | Insider transaction | Sep 16, 2024 | Sep 12, 2024 |
| 4 | Insider transaction | Sep 16, 2024 | Sep 12, 2024 |
| 4 | Insider transaction | Sep 16, 2024 | Sep 12, 2024 |
| 4 | Insider transaction | Sep 16, 2024 | Sep 12, 2024 |
| 4 | Insider transaction | Sep 16, 2024 | Sep 12, 2024 |
| 4 | Insider transaction | Sep 16, 2024 | Sep 16, 2024 |
| 4 | Insider transaction | Sep 16, 2024 | Sep 12, 2024 |
| 4 | Insider transaction | Sep 16, 2024 | Sep 12, 2024 |
| 4 | Insider transaction | Sep 16, 2024 | Sep 16, 2024 |
| 4 | Insider transaction | Sep 16, 2024 | Sep 12, 2024 |
| 4 | Insider transaction | Sep 16, 2024 | Sep 12, 2024 |
| 4 | Insider transaction | Sep 16, 2024 | Sep 12, 2024 |
| S-8 | Employee stock plan registration | Sep 16, 2024 | — |
| 8-K |
Current report
Bylaw or fiscal year change
|
Sep 16, 2024 | Sep 16, 2024 |
| 424B4 | Prospectus | Sep 13, 2024 | — |
| SEC STAFF LETTER | Filing | Sep 12, 2024 | — |
| EFFECT | Filing | Sep 12, 2024 | — |
| 3 | Initial insider ownership | Sep 12, 2024 | Sep 12, 2024 |
| 3 | Initial insider ownership | Sep 12, 2024 | Sep 12, 2024 |
| 3 | Initial insider ownership | Sep 12, 2024 | Sep 12, 2024 |
| 3 | Initial insider ownership | Sep 12, 2024 | Sep 12, 2024 |
| 3 | Initial insider ownership | Sep 12, 2024 | Sep 12, 2024 |
| 3 | Initial insider ownership | Sep 12, 2024 | Sep 12, 2024 |
| 3 | Initial insider ownership | Sep 12, 2024 | Sep 12, 2024 |
| 3 | Initial insider ownership | Sep 12, 2024 | Sep 12, 2024 |
| 3 | Initial insider ownership | Sep 12, 2024 | Sep 12, 2024 |
| 3 | Initial insider ownership | Sep 12, 2024 | Sep 12, 2024 |
| 3 | Initial insider ownership | Sep 12, 2024 | Sep 12, 2024 |
| 3 | Initial insider ownership | Sep 12, 2024 | Sep 12, 2024 |
| 3 | Initial insider ownership | Sep 12, 2024 | Sep 12, 2024 |
| 3 | Initial insider ownership | Sep 12, 2024 | Sep 12, 2024 |
| 3 | Initial insider ownership | Sep 12, 2024 | Sep 12, 2024 |
| S-1MEF | Filing | Sep 12, 2024 | — |
| CERT | Filing | Sep 12, 2024 | — |
| 8-A12B | Filing | Sep 10, 2024 | — |
| CORRESP | Letter to the SEC | Sep 10, 2024 | — |
| CORRESP | Letter to the SEC | Sep 10, 2024 | — |
| S-1/A | Amended registration statement | Sep 6, 2024 | — |
| CORRESP | Letter to the SEC | Aug 27, 2024 | — |
| S-1 | Registration statement | Aug 22, 2024 | — |
| DRSLTR | Filing | Jul 25, 2024 | — |
| UPLOAD | Letter from the SEC | Jul 24, 2024 | — |
| DRSLTR | Filing | Jul 16, 2024 | — |
| UPLOAD | Letter from the SEC | Jul 5, 2024 | — |
| DRSLTR | Filing | Jun 26, 2024 | — |
| DRS/A | Filing | Jun 26, 2024 | — |
| UPLOAD | Letter from the SEC | Jun 18, 2024 | — |
| DRSLTR | Filing | Jun 14, 2024 | — |
| DRS/A | Filing | Jun 14, 2024 | — |
| UPLOAD | Letter from the SEC | May 28, 2024 | — |
| DRS/A | Filing | May 16, 2024 | — |
| DRSLTR | Filing | May 15, 2024 | — |
| D | Filing | May 14, 2024 | — |
| SEC STAFF LETTER | Filing | Feb 21, 2024 | — |
| UPLOAD | Letter from the SEC | Feb 21, 2024 | — |
| DRS | Filing | Jan 25, 2024 | — |
| D | Filing | Nov 15, 2022 | — |
Showing 193 filings. Main filings leave out insider and ownership forms such as Form 4; choose a type above to see them. Each form opens on SEC.gov. Older filings are on SEC EDGAR.
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Company profile
- Industry
- Pharmaceutical Preparations (SIC 2834)
- Listed as
- ZBIO (Nasdaq)
- Fiscal year ends
- December 31
- Incorporated in
- DE
- Headquarters
- Waltham, MA
- SEC filer status
- Non-accelerated filer, Smaller reporting company, Emerging growth company
- SEC CIK
- 1953926
- Former names
- Zenas BioPharma (Cayman) Ltd (until Nov 15, 2022)
Other Pharmaceutical Preparations companies
- ELI LILLY & Co LLY
- Johnson & Johnson JNJ
- AbbVie Inc. ABBV
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- Abbott Laboratories ABT
- Novo Nordisk A S NVO
Source: SEC EDGAR filings. This is company-reported data, not investment advice.