Curbline Properties美股招股说明书(2026-06-29版)

Common Stock Curbline Properties Corp. We expect to enter into forward sale agreements with each of Goldman Sachs & Co. LLC, Morgan Stanley & Co. LLC and Wells Fargo Bank, National Association (the“forward purchasers”). In connection with the forward sale agreements, the forward purchasers or their affiliates are expected to borrow from third parties and to sell to theunderwriters an aggregate of 10,000,000shares of our common stock, $0.01 par value per share (“common stock”) (or an aggregate of 11,500,000shares if the underwriters’option to purchase additional shares is exercised in full) that will be delivered in this offering. We will not receive any proceeds from the sale of shares of our common stock by the forward purchasers or their affiliates. We expect to physically settle the forward saleagreements (by the delivery of shares of our common stock) and receive proceeds from the sale of those shares of our common stock upon one or more forward settlement dates,which we anticipate will be within approximately 18 months from the date of this prospectus supplement. We may also elect to cash settle or net share settle all or a portion of ourobligations under a forward sale agreement if we conclude it is in our best interest to do so. If we elect to cash settle a forward sale agreement, then we may not receive anyproceeds and may owe cash to the relevant forward purchaser in certain circumstances. If we elect to net share settle a forward sale agreement, then we will not receive anyproceeds and may owe shares of our common stock to the relevant forward purchaser in certain circumstances. See “Underwriting—Forward Sale Agreements.” If any forward purchaser or its affiliate does not deliver and sell all of the shares of our common stock to be delivered and sold by it on the anticipated closing date of thisoffering, then we will issue and sell to the underwriters a number of shares of our common stock equal to the number of shares of our common stock that such forward purchaseror its affiliate did not deliver and sell, and the number of shares underlying the relevant forward sale agreement will be decreased by the number of shares that we issue and sell. Our common stock is listed on the New York Stock Exchange (“NYSE”) under the symbol “CURB.” On June29, 2026, the last reported sale price of our common stock onthe NYSE was $31.27 per share. There are certain restrictions on transfer and ownership of our common stock intended to, among other things, preserve our qualification as a realestate investment trust (“REIT”) for federal income tax purposes. See “Description of Capital Stock—Restrictions on Ownership and Transfer” in the accompanying prospectus. Investing in our common stock involves risks. See the information under the caption “Risk Factors” beginning on pageS-6 of this prospectus supplement and the riskfactors in our Annual Report on Form 10-K for the year ended December31, 2025 filed with the Securities and Exchange Commission (“SEC”) and any risk factors set forth in thedocuments incorporated by reference into this prospectus supplement, concerning factors you should consider before making a decision to invest in our common stock. Neither the SEC nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanyingprospectus is truthful or complete. Any representation to the contrary is a criminal offense. Public offering price (2)We expect to receive net proceeds from the sale of the shares of our common stock, before estimated expenses, of approximately $million assuming full physicalsettlement of the forward sale agreements, which we anticipate will be within approximately 18 months from the date of this prospectus supplement. For the purposes ofcalculating the aggregate net proceeds to us, we have assumed that the forward sale agreements will be fully physically settled based on the initial forward sale price of$per share, which is the public offering price less the underwriting discount shown above. The forward sale price is subject to adjustment pursuant to the terms ofthe forward sale agreements, and the actual proceeds, if any, to us will be calculated as described in this prospectus supplement. Although we expect to settle the forwardsale agreements entirely by the full physical delivery of shares of our common stock in exchange for cash proceeds, we may elect cash settlement or net share settlement forall or a portion of our obligations under the forward sale agreements. See “Underwriting-Forward Sale Agreements” for a description of the forward sale agreements. The information in this preliminary prospectus supplement relates to an effective registration statement under the Securities Act of 1933, as amended,but is not complete and may be changed.The underwriters have been granted a 30-day option from the date of this prospectus supplement, exercisable in whole or in part from time to time, to purcha