Over-allotment sale brings ClearSign (CLIR) $470,858 in cash

Rhea-AI Filing Summary

ClearSign Technologies Corporation completed the sale of 116,667 additional shares of common stock through the full exercise of the underwriter’s over-allotment option, generating net proceeds of approximately $470,858.

These funds will be used for working capital, research and development, marketing and sales, and other general corporate purposes, adding to the company’s financial resources following its previously closed underwritten public offering of 777,780 shares at $4.33 per share.

8-K Event Classification

2 items: 8.01, 9.01

2 items

Item 8.01 Other Events Other

Voluntary disclosure of events the company deems important to shareholders but not covered by other items.

Item 9.01 Financial Statements and Exhibits Exhibits

Financial statements, pro forma financial information, and exhibit attachments filed with this report.

Key Figures

Additional shares sold: 116,667 shares Net proceeds from additional shares: $470,858 Firm Shares in original offering: 777,780 shares +2 more

5 metrics

Additional shares sold 116,667 shares Over-allotment option exercised on June 18, 2026

Net proceeds from additional shares $470,858 After underwriting discounts, commissions and estimated expenses

Firm Shares in original offering 777,780 shares Underwritten public offering of common stock

Public offering price $4.33 per share Price for Firm Shares in original offering

Over-allotment capacity Up to 116,667 shares 30-day over-allotment option granted to underwriter

Key Terms

firm-commitment underwritten public offering, Over-allotment Option, Form S-3, prospectus supplement, +1 more

5 terms

firm-commitment underwritten public offering financial

"relating to the Company’s firm-commitment underwritten public offering (the “Offering”)"

Over-allotment Option financial

"the Company also granted the Underwriter an option exercisable for thirty (30) days (the “Over-allotment Option”)"

An over-allotment option is a special agreement that allows underwriters to sell more shares than initially planned if demand is high. Think of it like a retailer offering extra units of a popular product to meet additional customer interest. This option helps ensure the full sale is completed and can also give investors extra shares if they want more.

Form S-3 regulatory

"pursuant to an effective registration statement on Form S-3 (File No. 333-288736)"

Form S-3 is a legal document companies use to register their stock sales with the government, making it easier and faster for them to raise money by selling shares to investors. It’s like having a pre-approved shopping list that lets a company quickly sell new shares when they need funds, without going through a lengthy approval process each time.

prospectus supplement regulatory

"as supplemented by a preliminary prospectus supplement, dated May 28, 2026, and a final prospectus supplement"

A prospectus supplement is an additional document provided alongside a company's main offering details, offering updated or extra information about a specific financial product being sold. It helps investors understand the latest terms, risks, and details of the investment, similar to how an update or revision clarifies or expands on original instructions, ensuring they have current and complete information before making a decision.

working capital financial

"use the net proceeds from the offer and sale of the Additional Shares for working capital, research and development"

Working capital is the money a business has available to cover its daily expenses, like paying bills and buying supplies. It’s like the cash in your wallet that helps you handle everyday costs; having enough ensures the business can operate smoothly without running into money shortages.

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

Understanding 8-K Material Events →

false 0001434524 0001434524 2026-06-18 2026-06-18 iso4217:USD xbrli:shares iso4217:USD xbrli:shares

UNITED STATES 

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of report (Date of earliest event reported): June 18, 2026

CLEARSIGN TECHNOLOGIES CORPORATION

(Exact name of registrant as specified in charter)

Delaware		001-35521		26-2056298
(State or other jurisdiction of incorporation)		(Commission File Number)		(IRS Employer Identification No.)

8023 E. 63rd Place, Suite 101

Tulsa, Oklahoma 74133

(Address of principal executive offices and zip code)

(918) 500-7312

(Registrant's telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the Registrant under any of the following provisions (see General Instruction A.2 below).

¨  Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR240.14a-12)

¨  Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨  Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class		Trading Symbol(s)		Name of each exchange on which registered
Common Stock		CLIR		The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ¨

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

Item 8.01 Other Events.

As previously disclosed in a Current Report on Form 8-K filed with the Securities and Exchange Commission (“SEC”) on June 1, 2026, ClearSign Technologies Corporation (the “Company”) entered into an underwriting agreement, dated May 28, 2026 (the “Underwriting Agreement”), with Newbridge Securities Corporation (the “Underwriter”), relating to the Company’s firm-commitment underwritten public offering (the “Offering”) for the issuance and sale of 777,780 shares (the “Firm Shares”) of the Company’s common stock, par value $0.0001 per share (the “Common Stock”), primarily to existing stockholders of the Company, at a public offering price of $4.33 per Firm Share, less underwriting discounts and commissions, pursuant to an effective registration statement on Form S-3 (File No. 333-288736) (the “Registration Statement”), including the prospectus forming a part of the Registration Statement, as supplemented by a preliminary prospectus supplement, dated May 28, 2026, and a final prospectus supplement, dated May 28, 2026, each filed with the SEC. Under the terms of the Underwriting Agreement, the Company also granted the Underwriter an option exercisable for thirty (30) days (the “Over-allotment Option”) to purchase up to an additional 116,667 shares of Common Stock (the “Additional Shares”) from the Company at the Firm Share price, less underwriting discounts and commissions, to cover over-allotments. The Offering closed on June 1, 2026.

On June 18, 2026, pursuant to the full exercise of the Over-allotment Option, the Underwriter purchased 116,667 Additional Shares, for net proceeds of approximately $470,858 after deducting underwriting discounts and commissions and estimated expenses payable by the Company. The Company intends to use the net proceeds from the offer and sale of the Additional Shares for working capital, research and development, marketing and sales, and general corporate purposes.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

Exhibit No.		Description
104		Cover Page Interactive Data File (embedded within the Inline XBRL document).

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Dated: June 18, 2026

	CLEARSIGN TECHNOLOGIES CORPORATION
	By:	/s/ Colin James Deller
	Name:	Colin James Deller
	Title:	Chief Executive Officer

FAQ

What did ClearSign Technologies (CLIR) announce in this 8-K?

ClearSign Technologies reported that its underwriter fully exercised an over-allotment option, purchasing 116,667 additional common shares. This follow-on sale brings in about $470,858 of net proceeds to support working capital, research and development, marketing and sales, and general corporate purposes.

How many additional ClearSign Technologies (CLIR) shares were sold?

The underwriter purchased 116,667 additional shares of ClearSign Technologies’ common stock. These shares were issued under an over-allotment option tied to a prior underwritten offering, using the same public offering price per share, less underwriting discounts and commissions.

How much cash did ClearSign Technologies (CLIR) receive from the over-allotment?

ClearSign Technologies received net proceeds of approximately $470,858 from the sale of 116,667 additional shares. This amount reflects deductions for underwriting discounts, commissions, and estimated expenses that the company is responsible for paying in connection with the transaction.

What is ClearSign Technologies (CLIR) using the new proceeds for?

The company plans to use the net proceeds primarily for working capital, research and development, marketing and sales, and general corporate purposes. These uses support ongoing operations and product development rather than a specific acquisition or one-time initiative.

How does this transaction relate to ClearSign Technologies’ earlier offering?

The additional shares were sold under an over-allotment option connected to a prior underwritten public offering of 777,780 common shares at $4.33 per share. The over-allotment option allowed the underwriter to buy extra shares on the same pricing terms.

Who acted as underwriter in ClearSign Technologies’ share sale?

Newbridge Securities Corporation served as the underwriter for ClearSign Technologies’ firm-commitment underwritten public offering. It also exercised the 30-day over-allotment option to buy 116,667 additional shares from the company on the agreed terms.

Filing Exhibits & Attachments

3 documents

Other Documents

• EX-101 XBRL TAXONOMY EXTENSION SCHEMA 2.9 KB
• EX-101 XBRL TAXONOMY EXTENSION LABEL LINKBASE 33.4 KB
• EX-101 XBRL TAXONOMY EXTENSION PRESENTATION LINKBASE 21.8 KB