ClearSign Technologies Corp SEC Filings

ClearSign Technologies (CLIR) reported a director equity grant on Form 4. On 10/01/2025, the reporting person acquired 26,830 restricted stock units (RSUs) at $0.00 as compensation for non‑executive director service for the quarter ending December 31, 2025. Each RSU represents the right to receive one share of common stock or the cash equivalent.

Following the transaction, 120,469 derivative securities were beneficially owned on a direct basis. The RSUs will vest upon the first to occur of a Change in Control, the reporting person’s Disability, death, or separation from service.

ClearSign Technologies Corporation received a second notice from Nasdaq on September 30, 2025 granting a 180-day extension, until March 30, 2026, to regain compliance with the $1.00 minimum bid price requirement for continued listing on the Nasdaq Capital Market. The company previously fell out of compliance after its stock traded below $1.00 for 30 consecutive business days ending March 31, 2025. ClearSign told Nasdaq it intends to regain compliance, including potentially effecting a reverse stock split if needed. If the closing bid price reaches at least $1.00 for 10 consecutive business days before the deadline, the company will be back in compliance. If it fails to do so, its common stock may be delisted, though ClearSign could appeal any delisting determination. For now, the extension has no immediate effect on the listing or trading of its shares, which continue to trade on Nasdaq under the symbol CLIR.

ClearSign Technologies Corporation reported changes to its board structure that restore compliance with Nasdaq’s director and audit committee independence rules. After two independent directors resigned in early August, the company had fallen out of compliance with Nasdaq Listing Rule 5605(b)(1) and 5605(c)(2)(A). On August 26, 2025, the board determined that director Anthony DiGiandomenico qualifies as an independent director under Nasdaq rules and appointed him to the Audit and Risk Committee. The board also named independent director G. Todd Silva as chair of the Audit Committee and designated him as the committee’s audit committee financial expert. Nasdaq subsequently confirmed on August 28, 2025 that ClearSign had regained compliance, although the board still plans to fill one remaining vacancy.

ClearSign Technologies (CLIR) filed a prospectus supplement describing an offering that would result in 57,693,504 shares of common stock outstanding assuming full exercise of the Warrants. The filing confirms the company’s common stock trades on Nasdaq under the symbol CLIR. The prospectus lists various dilutive instruments: restricted stock units (~1,077,000 shares), outstanding stock options (~2,397,000 shares at a weighted-average exercise price of $2.03), outside-plan options (~491,000 shares at $1.53), reserved plan shares (~1,692,000), consultant plan reserve (~278,000), underwriter warrants (425,109 shares at $1.1375), redeemable warrants (15,147,606 shares at $1.05), pre-funded warrants (2,795,395 at $0.0001), and placement agent warrants (432,432 at $1.1375). The prospectus references net tangible book value per share as of June 30, 2025 but does not state a figure in the provided excerpt. Two dates, May 15, 2025 and August 14, 2025, appear in the text.

ClearSign Technologies Corporation (CLIR) amended its S-1 registration, providing updated capital structure and exhibit information. The company states 57,693,504 shares of common stock would be outstanding immediately after this offering assuming full exercise of warrants. The prospectus discloses a net tangible book value per share of $0.18 as of June 30, 2025. The filing lists significant potential dilution: approximately 15,147,606 shares issuable upon exercise of certain redeemable warrants at $1.05, 2,795,395 shares from pre-funded warrants at $0.0001, and placement agent warrants for 432,432 shares. The document also updates exhibits and agreements incorporated by reference and notes the company’s Nasdaq ticker as CLIR.

ClearSign Technologies Corporation (CLIR) filed a Form 8-K disclosing the release of a press release and a conference call transcript dated August 14, 2025. The filing lists Items 2.02 (Results of Operations and Financial Condition), 7.01 (Regulation FD Disclosure) and 9.01 (Financial Statements and Exhibits) and identifies Exhibits 99.1 (press release) and 99.2 (conference call transcript). The cover page notes an Inline XBRL cover page file. The filing is signed by Colin James Deller, Chief Executive Officer. The document provides the existence and dates of disclosure materials but contains no operational metrics, earnings figures, transactions, or forward guidance in the text provided.

ClearSign Technologies Corporation filed a Form S-1 to register 5,267,222 shares of common stock issuable upon exercise of outstanding redeemable warrants issued in April 2024, each with an initial exercise price of $1.05 and a five-year term. If exercised in full, the company could receive up to approximately $5.5 million, which it expects to use for working capital, R&D, marketing and general purposes. The filing notes existing commercial deployments of its ClearSign Core(TM) combustion technology in refining, upstream oil production and boilers and describes potential heat-transfer efficiency gains and NOx emissions reductions versus legacy controls.

Key corporate and market items disclosed include a Nasdaq listing under symbol CLIR (last reported sale $0.54 on August 11, 2025), a Nasdaq bid-price noncompliance notice with a cure period through September 29, 2025, and a separate Nasdaq composition notice regarding board independence and Audit Committee composition. The company also terminated a prior ATM and entered a new ATM with H.C. Wainwright for up to $10.39 million under an S-3 declared effective July 28, 2025. The registration also quantifies existing dilution vectors, including large outstanding warrant and option pools.

ClearSign Technologies disclosed that Nasdaq notified the company it is not in compliance with board independence and audit committee composition rules following the resignations of Catharine M. de Lacy and Judith S. Schrecker, which became effective August 4, 2025. At the time of the notice the Board lacked a majority of independent directors and the Audit and Risk Committee had only two independent members instead of the required three. The Board reduced its size from six to five, appointed Louis J. Basenese to the Governance Committee and G. Todd Silva to the Compensation Committee, and does not currently intend to appoint a lead independent director. The company intends to appoint an independent director who meets Nasdaq and Rule 10A-3 requirements to regain compliance. Nasdaq granted a cure period until the earlier of the next annual meeting or August 4, 2026 (with an alternative February 2, 2026 deadline if the annual meeting occurs earlier). The Notice does not affect the immediate listing of the company’s common stock, and a press release is furnished as Exhibit 99.1.