Offerings // X4 Pharmaceuticals, Inc

XFOR offering history

Every offering-related filing in X4 Pharmaceuticals, Inc’s recent SEC record — registrations (announced capacity) kept separate from pricing documents (executed sales). Reviewed 806 filings back to Sep 24, 2010.

Last executed offering

Oct 24, 2025

424B5 — priced deal (shares or notes)

Last registration (announced)

May 6, 2026

S-3 — capacity, not a sale

Executed, last 12 months

424B pricings + 8-K 3.02 sales

Registered, last 12 months

S-1/S-3/F-series registrations

Date	Filing		What it means
May 14, 2026	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
May 6, 2026	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Oct 24, 2025	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Oct 23, 2025	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Sep 18, 2025	424B3 →	UPDATE	Prospectus update — often a resale registration, not necessarily new capital
Sep 17, 2025	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Sep 10, 2025	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Aug 13, 2025	8-K →	EXECUTED	Unregistered share sale disclosed (8-K item 3.02)
Aug 12, 2025	8-K →	EXECUTED	Unregistered share sale disclosed (8-K item 3.02)
Jun 23, 2025	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Aug 24, 2023	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Aug 14, 2023	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Jun 21, 2023	424B3 →	UPDATE	Prospectus update — often a resale registration, not necessarily new capital
Jun 20, 2023	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Jun 9, 2023	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
May 16, 2023	8-K →	EXECUTED	Unregistered share sale disclosed (8-K item 3.02)
Dec 9, 2022	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Dec 7, 2022	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Aug 5, 2022	424B3 →	UPDATE	Prospectus update — often a resale registration, not necessarily new capital
Aug 5, 2022	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Jul 29, 2022	424B3 →	UPDATE	Prospectus update — often a resale registration, not necessarily new capital
Jul 29, 2022	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Jul 1, 2022	8-K →	EXECUTED	Unregistered share sale disclosed (8-K item 3.02)
May 13, 2022	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Apr 22, 2022	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Mar 22, 2022	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Mar 3, 2022	8-K →	EXECUTED	Unregistered share sale disclosed (8-K item 3.02)
Jan 14, 2022	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Jan 4, 2022	424B3 →	UPDATE	Prospectus update — often a resale registration, not necessarily new capital
Jan 3, 2022	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Dec 23, 2021	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Nov 5, 2021	8-K →	EXECUTED	Unregistered share sale disclosed (8-K item 3.02)
Jul 12, 2021	424B3 →	UPDATE	Prospectus update — often a resale registration, not necessarily new capital
Jul 9, 2021	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Jun 25, 2021	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Mar 19, 2021	8-K →	EXECUTED	Unregistered share sale disclosed (8-K item 3.02)
Oct 26, 2020	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Oct 19, 2020	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Oct 16, 2020	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Aug 19, 2020	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin

XFOR offering-related filings from SEC EDGAR, newest first (capped at 40). Each links to the original document.

Two honest limits. (1) A 424B takedown can price shares or notes— EDGAR’s metadata doesn’t say which, so open the document: large investment-grade filers use these mostly for bond deals (no dilution), small-caps mostly for shares. (2) At-the-market (ATM) programs sell shares gradually and individual sales are not separately filed — the visible footprint is the enabling shelf and its 424B5; actual ATM share counts surface later in the 10-Q/10-K share count. Educational information from public filings, not investment advice.

Is a shelf active now? →Do they need money? →Red flags →Full XFOR workspace →

XFOR offering FAQ

When did XFOR last execute an offering?

Per SEC filings, X4 Pharmaceuticals, Inc's most recent priced offering document is a 424B5 filed 2025-10-24. Note a 424B takedown can price shares or notes (debt) — the linked document says which.

When did XFOR last announce or register an offering?

The most recent registration is a S-3 filed 2026-05-06. A registration is capacity to sell shares — not a sale.

Does an offering always mean dilution?

Registered direct offerings and shelf takedowns issue new shares and dilute existing holders. Resale registrations (424B3/B7) let existing holders sell and do not create new shares. Secondary sales by insiders also do not dilute. Each row here is labeled with what it is.