Offerings // AMTECH SYSTEMS INC

ASYS offering history

Every offering-related filing in AMTECH SYSTEMS INC’s recent SEC record — registrations (announced capacity) kept separate from pricing documents (executed sales). Reviewed 978 filings back to May 15, 1995.

Last executed offering

Jun 3, 2026

424B5 — priced deal (shares or notes)

Last registration (announced)

Jun 1, 2026

S-3MEF — 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
Jun 3, 2026	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Jun 1, 2026	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Jun 1, 2026	S-3MEF →	REGISTERED	S-3MEF registration — capacity to sell shares, not a sale yet
Mar 23, 2026	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Mar 13, 2026	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Aug 18, 2017	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Aug 17, 2017	424B5 →	EXECUTED	Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Feb 6, 2017	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Feb 2, 2017	S-3/A →	REGISTERED	S-3/A registration — capacity to sell shares, not a sale yet
Jan 18, 2017	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Dec 23, 2014	424B3 →	UPDATE	Prospectus update — often a resale registration, not necessarily new capital
Dec 22, 2014	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Jan 23, 2012	RW →	WITHDRAWN	Registration withdrawn
Sep 14, 2011	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Sep 9, 2011	RW →	WITHDRAWN	Registration withdrawn
Aug 12, 2011	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
May 13, 2011	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Feb 8, 2011	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Nov 16, 2007	424B1 →	EXECUTED	Prospectus supplement priced — shares or notes (large filers: often a bond deal)
Nov 15, 2007	S-1MEF →	REGISTERED	S-1MEF registration — capacity to sell shares, not a sale yet
Nov 15, 2007	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Nov 13, 2007	S-1/A →	REGISTERED	S-1/A registration — capacity to sell shares, not a sale yet
Nov 7, 2007	S-1/A →	REGISTERED	S-1/A registration — capacity to sell shares, not a sale yet
Oct 23, 2007	S-1 →	REGISTERED	S-1 registration — capacity to sell shares, not a sale yet
Feb 1, 2007	S-1MEF →	REGISTERED	S-1MEF registration — capacity to sell shares, not a sale yet
Feb 1, 2007	424B1 →	EXECUTED	Prospectus supplement priced — shares or notes (large filers: often a bond deal)
Jan 31, 2007	EFFECT →	EFFECTIVE	SEC declared a registration effective — selling can begin
Jan 30, 2007	S-1/A →	REGISTERED	S-1/A registration — capacity to sell shares, not a sale yet
Jan 16, 2007	S-1/A →	REGISTERED	S-1/A registration — capacity to sell shares, not a sale yet
Dec 22, 2006	S-1 →	REGISTERED	S-1 registration — capacity to sell shares, not a sale yet
Mar 23, 2006	8-K →	EXECUTED	Unregistered share sale disclosed (8-K item 3.02)
Feb 3, 2006	424B3 →	UPDATE	Prospectus update — often a resale registration, not necessarily new capital
Jan 13, 2006	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Apr 28, 2005	8-K →	EXECUTED	Unregistered share sale disclosed (8-K item 3.02)
Oct 31, 2000	424B3 →	UPDATE	Prospectus update — often a resale registration, not necessarily new capital
Oct 2, 2000	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Aug 14, 1996	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet
Aug 9, 1996	S-3 →	REGISTERED	S-3 registration — capacity to sell shares, not a sale yet

ASYS 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 ASYS workspace →

ASYS offering FAQ

When did ASYS last execute an offering?

Per SEC filings, AMTECH SYSTEMS INC's most recent priced offering document is a 424B5 filed 2026-06-03. Note a 424B takedown can price shares or notes (debt) — the linked document says which.

When did ASYS last announce or register an offering?

The most recent registration is a S-3MEF filed 2026-06-01. 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.