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Offerings // ClearSign Technologies Corp

CLIR offering history

Every offering-related filing in ClearSign Technologies Corp’s recent SEC record — registrations (announced capacity) kept separate from pricing documents (executed sales). Reviewed 784 filings back to May 5, 2008.

Last executed offering
Jul 23, 2026
8-K — priced deal (shares or notes)
Last registration (announced)
Aug 20, 2025
S-1/A — capacity, not a sale
Executed, last 12 months
5
424B pricings + 8-K 3.02 sales
Registered, last 12 months
2
S-1/S-3/F-series registrations
DateFilingWhat it means
Jul 23, 20268-KEXECUTEDUnregistered share sale disclosed (8-K item 3.02)
Jul 6, 2026424B5EXECUTEDShelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Jun 1, 2026424B5EXECUTEDShelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
May 28, 2026424B5EXECUTEDShelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Aug 22, 2025424B4EXECUTEDFinal prospectus — offering priced (typical for IPOs and marketed share deals)
Aug 21, 2025EFFECTEFFECTIVESEC declared a registration effective — selling can begin
Aug 20, 2025S-1/AREGISTEREDS-1/A registration — capacity to sell shares, not a sale yet
Aug 12, 2025S-1REGISTEREDS-1 registration — capacity to sell shares, not a sale yet
Jul 28, 2025EFFECTEFFECTIVESEC declared a registration effective — selling can begin
Jul 17, 2025S-3REGISTEREDS-3 registration — capacity to sell shares, not a sale yet
Jul 15, 2024424B4EXECUTEDFinal prospectus — offering priced (typical for IPOs and marketed share deals)
Jul 12, 2024EFFECTEFFECTIVESEC declared a registration effective — selling can begin
Jul 3, 2024S-1/AREGISTEREDS-1/A registration — capacity to sell shares, not a sale yet
Jun 26, 20248-KEXECUTEDUnregistered share sale disclosed (8-K item 3.02)
May 20, 2024S-1REGISTEREDS-1 registration — capacity to sell shares, not a sale yet
May 10, 20248-KEXECUTEDUnregistered share sale disclosed (8-K item 3.02)
Apr 23, 2024424B5EXECUTEDShelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Apr 23, 20248-KEXECUTEDUnregistered share sale disclosed (8-K item 3.02)
Apr 19, 2024424B5EXECUTEDShelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Apr 19, 20248-KEXECUTEDUnregistered share sale disclosed (8-K item 3.02)
Mar 19, 2024FWPMARKETINGFree-writing prospectus — offering being marketed
Mar 18, 2024424B5EXECUTEDShelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Mar 18, 2024424B5EXECUTEDShelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Sep 1, 2023424B3UPDATEProspectus update — often a resale registration, not necessarily new capital
Aug 30, 2023EFFECTEFFECTIVESEC declared a registration effective — selling can begin
Aug 11, 2023S-3REGISTEREDS-3 registration — capacity to sell shares, not a sale yet
Aug 12, 2022EFFECTEFFECTIVESEC declared a registration effective — selling can begin
Jul 29, 2022S-3/AREGISTEREDS-3/A registration — capacity to sell shares, not a sale yet
Jul 1, 2022S-3REGISTEREDS-3 registration — capacity to sell shares, not a sale yet
May 31, 2022424B5EXECUTEDShelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
May 26, 2022424B5EXECUTEDShelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Apr 14, 2022424B5EXECUTEDShelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Dec 23, 2020424B5EXECUTEDShelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)
Aug 21, 2020424B2EXECUTEDProspectus supplement priced — shares or notes (large filers: often a bond deal)
Aug 19, 2020424B2EXECUTEDProspectus supplement priced — shares or notes (large filers: often a bond deal)
Jul 12, 2019EFFECTEFFECTIVESEC declared a registration effective — selling can begin
Jun 27, 2019S-3REGISTEREDS-3 registration — capacity to sell shares, not a sale yet
Sep 24, 2018424B3UPDATEProspectus update — often a resale registration, not necessarily new capital
Sep 21, 2018EFFECTEFFECTIVESEC declared a registration effective — selling can begin
Aug 31, 2018S-3REGISTEREDS-3 registration — capacity to sell shares, not a sale yet
CLIR 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 CLIR workspace →
CLIR offering FAQ

When did CLIR last execute an offering?

Per SEC filings, ClearSign Technologies Corp's most recent priced offering document is a 8-K filed 2026-07-23. Note a 424B takedown can price shares or notes (debt) — the linked document says which.

When did CLIR last announce or register an offering?

The most recent registration is a S-1/A filed 2025-08-20. 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.