Offerings // CytomX Therapeutics, Inc.

CTMX offering history

Every offering-related filing in CytomX Therapeutics, Inc.’s recent SEC record — registrations (announced capacity) kept separate from pricing documents (executed sales). Reviewed 797 filings back to Sep 28, 2010.

Last executed offering

Mar 18, 2026

424B5 — priced deal (shares or notes)

Last registration (announced)

Mar 16, 2026

S-3ASR — 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
Mar 18, 2026	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Mar 16, 2026	S-3ASR →	REGISTERED	Automatic shelf registration — effective immediately (large filers)
Mar 16, 2026	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Aug 18, 2025	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Aug 7, 2025	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
May 12, 2025	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Aug 19, 2024	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Aug 9, 2024	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Aug 28, 2023	424B3 →	UPDATE	Prospectus update — often a resale registration, not necessarily new capital
Aug 25, 2023	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Aug 16, 2023	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Jul 3, 2023	8-K →	EXECUTED	Unregistered share sale disclosed (8-K item 3.02)
Mar 4, 2022	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Aug 18, 2021	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Aug 17, 2021	S-3/A →	REGISTERED	S-3/A registration — capacity to sell shares, not a sale yet
Aug 5, 2021	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Jan 21, 2021	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Jan 19, 2021	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Feb 27, 2020	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Apr 8, 2019	8-K →	EXECUTED	Unregistered share sale disclosed (8-K item 3.02)
Feb 11, 2019	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Feb 6, 2019	S-3/A →	REGISTERED	S-3/A registration — capacity to sell shares, not a sale yet
Nov 6, 2018	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Jul 13, 2018	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Jul 10, 2018	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Oct 3, 2017	8-K →	EXECUTED	Unregistered share sale disclosed (8-K item 3.02)
Mar 20, 2017	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Mar 9, 2017	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Dec 7, 2016	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Nov 23, 2016	S-3/A →	REGISTERED	S-3/A registration — capacity to sell shares, not a sale yet
Nov 3, 2016	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Oct 8, 2015	424B4 →	EXECUTED	Final prospectus — offering priced (typical for IPOs and marketed share deals)
Oct 7, 2015	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Oct 6, 2015	S-1/A →	REGISTERED	S-1/A registration — capacity to sell shares, not a sale yet
Oct 2, 2015	S-1/A →	REGISTERED	S-1/A registration — capacity to sell shares, not a sale yet
Sep 28, 2015	S-1/A →	REGISTERED	S-1/A registration — capacity to sell shares, not a sale yet
Sep 18, 2015	S-1/A →	REGISTERED	S-1/A registration — capacity to sell shares, not a sale yet
Sep 11, 2015	S-1/A →	REGISTERED	S-1/A registration — capacity to sell shares, not a sale yet
Aug 28, 2015	S-1 →	REGISTERED	S-1 registration — capacity to sell shares, not a sale yet

CTMX 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 CTMX workspace →

CTMX offering FAQ

When did CTMX last execute an offering?

Per SEC filings, CytomX Therapeutics, Inc.'s most recent priced offering document is a 424B5 filed 2026-03-18. Note a 424B takedown can price shares or notes (debt) — the linked document says which.

When did CTMX last announce or register an offering?

The most recent registration is a S-3ASR filed 2026-03-16. 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.