Horizon Space Acquisition II Corp美股招股说明书(2026-01-13版)

The board of directors of Horizon Space AcquisitionII Corp., a Cayman Islands exempted companylimited by shares (“HSPT”), has unanimously approved the Business Combination Agreement, dated May9,2025 (as may be amended, supplemented, or otherwise modified from time to time, the “Business CombinationAgreement”), by and among SL Science Holding Limited, a Cayman Islands exempted company limited byshares (“PubCo”), HSPT, CW Mega Limited, a Cayman Islands exempted company limited by shares and awholly-owned subsidiary of PubCo (“Merger SubI”), WW Century Limited, a Cayman Islands exemptedcompany limited by shares and a wholly-owned subsidiary of PubCo (“Merger SubII”), and SL BIO Ltd., aCayman Islands exempted company limited by shares (“SL Bio” or the “Company”), pursuant to which, amongother things, (i)Merger SubI will merge with and into HSPT, with HSPT as the surviving entity and a wholly-owned subsidiary of PubCo (the “First Merger”), and (ii)following the First Merger, Merger SubII will mergewith and into SL Bio, with SL Bio as the surviving entity and a wholly-owned subsidiary of PubCo (the“Second Merger,” and together with the First Merger and the other transactions contemplated by the BusinessCombination Agreement, the “Business Combination”). Upon the consummation of the Business Combination,each of HSPT and SL Bio will become a subsidiary of PubCo, and HSPT’s shareholders and SL Bio’sshareholders will receive ordinary shares of par value of $0.00001 each of PubCo (“PubCo Ordinary Shares”).The closing date of each of the First Merger and the Second Merger is hereinafter referred to as the “FirstClosing Date” and the “Second Closing Date” respectively. The Company expects PubCo Ordinary Shares belisted and traded on the Nasdaq Stock Market LLC (“Nasdaq”) following the consummation of the BusinessCombination. Pursuant to the Business Combination Agreement, (i)immediately prior to the First Merger Effective Time, a.eachAcquiror Unit(as defined in the Business Combination Agreement)issued andoutstanding immediately prior to the First Merger Effective Time (as defined in the BusinessCombination Agreement) will be automatically detached and the holder thereof will bedeemed to hold one (1)Acquiror Ordinary Share (as defined in the Business CombinationAgreement) and one (1)Acquiror Right (as defined in the Business Combination Agreement)in accordance with the terms of the applicable Acquiror Unit (the “Unit Separation”);b.each Acquiror Right issued and outstanding immediately prior to the First Merger EffectiveTime will be automatically converted into one-tenth (1/10) of an Acquiror Ordinary Share (the“Acquiror Right Conversion”);c.immediately following the Unit Separation and Acquiror Right Conversion, each AcquirorOrdinary Share (which, for the avoidance of doubt, includes the Acquiror Ordinary Sharesheld as a result of the Unit Separation and the Acquiror Right Conversion) issued andoutstanding immediately prior to the First Merger Effective Time will automatically becancelled and cease to exist in exchange for the right to receive one (1)newly issued PubCoOrdinary Share. (ii)at the Second Merger Effective Time (as defined in the Business Combination Agreement), eachCompanyExchanging Share(as defined in the Business Combination Agreement)willautomatically be cancelled and converted into the right of each holder of the Company ExchangingShares to receive, such number of newly issued PubCo Ordinary Shares, as determined inaccordance with the Business Combination Agreement, based on an exchange ratio equal to thequotient of (a) $5.568 billion divided by $10.00 per share, divided by (b) the number of the ordinaryshares, par value $0.1, of the Company (“Company Ordinary Shares”) issued and outstandingimmediately prior to the Second Merger Effective Time. Pursuant to the currently effective Amended and Restated Memorandum and Articles of Association,adopted by special resolution dated November12, 2024 (the “Existing HSPT Charter”), we have until February18, 2026 to consummate the Business Combination (or May18, 2026, if fully extended pursuant to the ExistingHSPT Charter). For details on the transactions involved in the Business Combination, see “Questions and Answers aboutthe Proposals—What is expected to happen in the Business Combination?” For impacts of dilution resultingfrom the consummation of the Business Combination on the non-redeeming HSPT shareholders who hold HSPT’s securities until the consummation of the Business Combination, see “Questions and Answers about theProposals—What shall be the relative equity stakes of HSPT shareholders, and SL Bio shareholders in PubCoupon completion of the Business Combination?” Table of Contents HSPT shareholders are being asked to consider a vote upon the Business Combination and certainproposalsrelated thereto as described in this proxy statement/prospectus.As a result of,and uponconsummation of the Business Combination, both HSPT and SL Bio will become sub