SeaStar Medical Holding Corp美股市值招股说明书(2025-10-14版)

SeaStar Medical Holding Corporation Up to $2,279,989 ofCommon Stock We previously entered into an at the market offering agreement (the “Offering Agreement”), dated August 20, 2024, with H.C.Wainwright & Co., LLC, as sales agent (the “Sales Agent” or “Wainwright”), relating to the sale of our common stock, par value$0.0001 per share (“Common Stock”), offered by this prospectus supplement and the accompanying base prospectus. In accordancewith the terms of the Offering Agreement and this prospectus supplement and the accompanying base prospectus, we may offer andsell shares of our Common Stock pursuant to this prospectus supplement having an aggregate offering price of up to $2,279,989 fromtime to time through Wainwright acting as our sales agent. Sales of our Common Stock, if any, under this prospectus supplement and the accompanying base prospectus may be made by anymethod permitted by law deemed to be “at-the-market” offerings as defined in Rule 415 promulgated under the Securities Act of 1933,as amended (the “Securities Act”), including, without limitation, sales made directly on or through the Nasdaq Capital Market(“Nasdaq”), the existing trading market for our Common Stock, or any other existing trading market in the United States for ourCommon Stock, sales made to or through a market maker other than on an exchange or otherwise, directly to the Sales Agent asprincipal in negotiated transactions at market prices prevailing at the time of sale or at prices related to such prevailing market prices,and/or in any other method permitted by law. If we and Wainwright agree on any method of distribution other than sales of shares ofour Common Stock on Nasdaq or another existing trading market in the United States at market prices, we will file a furtherprospectus supplement providing all information about such offering as required by Rule 424(b) under the Securities Act. Wainwrightis not required to sell any specific number or dollar amount of shares, but will act as a sales agent and use commercially reasonableefforts to sell on our behalf all of the shares of Common Stock requested to be sold by us, consistent with its normal trading and salespractices, on mutually agreed terms between Wainwright and us. There is no arrangement for funds to be received in any escrow, trustor similar arrangement. There is no minimum offering requirement. We provide more information about how the shares of CommonStock will be sold in the section entitled “Plan of Distribution.” Wainwright will be entitled to compensation at a fixed cash commission rate of 3.0% of the gross sales price of the shares sold by itunder the Offering Agreement. In connection with the sale of Common Stock on our behalf, Wainwright will be deemed to be an“underwriter” within the meaning of the Securities Act and the compensation of Wainwright will be deemed to be underwritingcommissions or discounts. We provide more information about our compensation arrangements with the Sales Agent in the sectionentitled “Plan of Distribution.” We have also agreed to provide indemnification and contribution to Wainwright with respect to certainliabilities, including liabilities under the Securities Act. This offering pursuant to this prospectus supplement will terminate upon thetermination by us or Wainwright of the Offering Agreement pursuant to its terms. The aggregate market value of our outstanding Common Stock held by non-affiliates is $42,019,639, based on 33,886,805 shares ofoutstanding Common Stock held by non-affiliates as of October 3 2025 and a price per share of $1.24, the closing price of ourCommon Stock on September 24, 2025. Pursuant to General Instruction I.B.6 of Form S-3, in no event will we offer to sell, pursuantto the registration statement of which this prospectus supplement forms a part, securities in a public primary offering with a valueexceeding one-third of our public float in any 12-month period so long as the aggregate market value of our outstanding CommonStock held by non-affiliates remains below $75 million. During the prior 12-calendar-month period that ends on, and includes, the dateof this prospectus supplement, we have sold $11,726,556 of shares of Common Stock pursuant to General Instruction I.B.6 of Form S-3. Our Common Stock is traded on The Nasdaq Capital Market (“Nasdaq”) under the symbol “ICU.” Our 10,550,000 listed warrants(which do not include the Purchase Warrants sold in the concurrent private placement) (the “Listed Warrants”) are traded on TheNasdaq Capital Market (“Nasdaq”) under the symbol “ICUCW.” On October 10, 2025, the last reported sale price on Nasdaq of ourCommon Stock was $0.5716 per share and the closing price of our Listed Warrants was $0.0301 per warrant. On July 31, 2025, we received a letter from Nasdaq notifying us that we were not in compliance with the $1.00 per share minimum bidprice requirement (the “Bid Price Requirement”) for continued inclusion on Nasdaq pursuant to Nasdaq Listing Rule 5550