X4 Pharmaceuticals, Inc SEC filings XFOR
X4 Pharmaceuticals, Inc has 818 filings in SEC EDGAR's recent list, going back to Sep 24, 2010. Its latest annual report, Form ARS, was filed on Mar 20, 2026 for the period ended Dec 31, 2025. The latest quarterly report (Form 10-Q) was filed on Nov 4, 2026, covering the quarter ended Sep 30, 2026. The most recent current report (Form 8-K) was filed on Oct 29, 2026 (other events). The company's fiscal year ends on December 31.
| Form | Description | Filed | Period |
|---|---|---|---|
| S-3 | Shelf registration | May 6, 2026 | — |
| S-8 | Employee stock plan registration | Mar 18, 2026 | — |
| 424B5 | Prospectus supplement | Oct 24, 2025 | — |
| 424B5 | Prospectus supplement | Oct 23, 2025 | — |
| 424B3 | Prospectus | Sep 18, 2025 | — |
| S-3 | Shelf registration | Sep 10, 2025 | — |
| S-8 | Employee stock plan registration | Sep 10, 2025 | — |
| 424B5 | Prospectus supplement | Jun 23, 2025 | — |
| S-8 | Employee stock plan registration | Mar 26, 2025 | — |
| S-8 | Employee stock plan registration | Jan 16, 2025 | — |
| S-8 | Employee stock plan registration | Oct 4, 2024 | — |
| S-8 | Employee stock plan registration | Jan 25, 2024 | — |
| S-3 | Shelf registration | Aug 14, 2023 | — |
| S-8 | Employee stock plan registration | Aug 14, 2023 | — |
| 424B3 | Prospectus | Jun 21, 2023 | — |
| S-3 | Shelf registration | Jun 9, 2023 | — |
| S-8 | Employee stock plan registration | Jan 20, 2023 | — |
| 424B5 | Prospectus supplement | Dec 9, 2022 | — |
| 424B5 | Prospectus supplement | Dec 7, 2022 | — |
| 424B3 | Prospectus | Aug 5, 2022 | — |
| S-3 | Shelf registration | Jul 29, 2022 | — |
| 424B3 | Prospectus | Jul 29, 2022 | — |
| S-3 | Shelf registration | Apr 22, 2022 | — |
| 424B5 | Prospectus supplement | Mar 22, 2022 | — |
| S-8 | Employee stock plan registration | Mar 10, 2022 | — |
| 424B5 | Prospectus supplement | Jan 14, 2022 | — |
| 424B3 | Prospectus | Jan 4, 2022 | — |
| S-3 | Shelf registration | Dec 23, 2021 | — |
| 424B3 | Prospectus | Jul 12, 2021 | — |
| S-3 | Shelf registration | Jun 25, 2021 | — |
| S-8 | Employee stock plan registration | Mar 23, 2021 | — |
| S-3 | Shelf registration | Oct 19, 2020 | — |
| 424B5 | Prospectus supplement | Oct 16, 2020 | — |
| S-3 | Shelf registration | Aug 7, 2020 | — |
| S-8 | Employee stock plan registration | Jun 10, 2020 | — |
| S-8 | Employee stock plan registration | Mar 13, 2020 | — |
| 424B5 | Prospectus supplement | Nov 27, 2019 | — |
| FWP | Free writing prospectus | Nov 26, 2019 | — |
| 424B5 | Prospectus supplement | Nov 25, 2019 | — |
| S-3/A | Filing | Aug 22, 2019 | — |
| S-8 | Employee stock plan registration | Aug 9, 2019 | — |
| S-3 | Shelf registration | Aug 9, 2019 | — |
| 424B5 | Prospectus supplement | Apr 15, 2019 | — |
| FWP | Free writing prospectus | Apr 12, 2019 | — |
| 424B5 | Prospectus supplement | Apr 12, 2019 | — |
| S-8 | Employee stock plan registration | Mar 25, 2019 | — |
| S-8 | Employee stock plan registration | Mar 11, 2019 | — |
| 424B3 | Prospectus | Feb 14, 2019 | — |
| S-4/A | Filing | Feb 13, 2019 | — |
| S-3 | Shelf registration | Jan 25, 2019 | — |
| S-4 | Registration for a merger or exchange | Dec 20, 2018 | — |
| S-8 | Employee stock plan registration | Mar 9, 2018 | — |
| 424B1 | Filing | Nov 17, 2017 | — |
| S-8 | Employee stock plan registration | Nov 16, 2017 | — |
| S-1/A | Amended registration statement | Nov 15, 2017 | — |
| S-1/A | Amended registration statement | Nov 6, 2017 | — |
| S-1 | Registration statement | Oct 20, 2017 | — |
Showing 57 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
- Biological Products, (No Diagnostic Substances) (SIC 2836)
- Listed as
- XFOR (Nasdaq)
- Fiscal year ends
- December 31
- Incorporated in
- DE
- Headquarters
- Boston, MA
- SEC filer status
- Non-accelerated filer, Smaller reporting company
- SEC CIK
- 1501697
- Former names
- Arsanis, Inc. (until Mar 13, 2019)
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All 182 Biological Products, (No Diagnostic Substances) companies
Source: SEC EDGAR filings. This is company-reported data, not investment advice.