Horizon Space Acquisition II Corp

Company identity and purpose

• Horizon Space Acquisition II Corp is a Cayman Islands exempted company formed on March 21, 2023.
• It is a special purpose acquisition company (SPAC) formed to complete a merger, share exchange, asset acquisition, share purchase, recapitalization, reorganization or similar business combination with one or more businesses.
• The Company may pursue opportunities globally and may pursue opportunities in China, including Hong Kong and Macau.

Capital raise and funds

• IPO: On November 18, 2024, the Company issued 6,000,000 units at $10.00 per unit, generating $60,000,000.
• Private placement at IPO: 200,000 private units were sold to the Sponsor (Horizon Space Acquisition II Sponsor Corp.) at $10.00 per unit, generating $2,000,000.
• Over-Allotment: The underwriters’ option to purchase up to 900,000 additional units was exercised in full, generating $9,000,000.
• Additional Private Units: Concurrent with the option exercise, the Company privately placed 13,500 private units to the Sponsor for $135,000.
• Trust account: Proceeds of $69,000,000 from the IPO, the sale of the Option Units, and the sale of Private Units were placed in a Trust Account held by Wilmington Trust, N.A. for the benefit of public shareholders and the underwriters.
• Representative shares: 241,500 ordinary shares were issued to the Representative in connection with the IPO and the option exercise.
• PIPE (post-signing) potential: In the SL Bio Business Combination, PubCo expects to issue 780,000 PubCo Units in a private placement at $10.00 per PubCo Unit. Each PubCo Unit will consist of one PubCo Ordinary Share and one Series A PubCo preferred share convertible into one-third of a PubCo Ordinary Share after six months. Approximate gross proceeds from the PIPE are expected to be $7,800,000.

Use of funds and liquidity

• Public cash proceeds held in the Trust Account are intended to be applied toward consummating a business combination and working capital.
• Private Units and PIPE arrangements involve funds outside the Trust Account.
• The Company has relied on the sale of securities and loans from the Sponsor and other parties to fund operations.

Business operations and model

• Since the IPO, the Company’s sole business activity has been identifying and evaluating suitable acquisition targets.
• Revenue: The Company has no revenue.
• Profit/loss: The Company has incurred losses since inception from formation and operating costs.
• Employees: The Company has two executive officers (CEO and CFO) and does not intend to have full-time employees prior to a business combination.

Management and governance

• Chief Executive Officer and Chairman: Mingyu (Michael) Li
• Chief Financial Officer: Min (Lydia) Zhai
• Directors: Mingyu (Michael) Li is the sole director of the Sponsor. Post-merger board composition will be determined by PubCo governance.

Recent development: SL Bio Business Combination

• On May 9, 2025, the Company entered into a Business Combination Agreement with SL Science Holding Limited (PubCo), CW Mega Limited (Merger Sub I), WW Century Limited (Merger Sub II), and SL Bio Ltd. (the target).
• Transaction structure:
  • First Merger: Merger Sub I will merge with the Company, with the Company surviving as a subsidiary of PubCo.
  • Second Merger: Merger Sub II will merge with SL Bio, with SL Bio surviving as a subsidiary of PubCo.
  • Post-transaction: The Company and SL Bio will become subsidiaries of PubCo. PubCo Ordinary Shares will be issued to the shareholders of the Company and SL Bio as consideration, and PubCo Ordinary Shares will be listed on Nasdaq after closing.
• PIPE financing for the Business Combination: PIPE investors have committed to purchase an aggregate of 780,000 PubCo Units at $10.00 per unit in a private placement; each PubCo Unit includes one PubCo Ordinary Share and one Series A PubCo preferred share (convertible into 1/3 of a PubCo Ordinary Share after six months).
• Regulatory filings and approvals: PubCo filed Form F-4 (effective January 13, 2026) and a Proxy Statement for an Extraordinary General Meeting (EGM). An EGM was held on February 12, 2026, where shareholders approved the Business Combination proposals, amendments to PubCo’s charter, and the appointment of a sole director for HSPT (effective at First Merger). A redemption of 3,502,404 ordinary shares of HSPT was approved in connection with the Business Combination.
• Redemption rights: HSPT public shareholders have redemption rights in connection with the Business Combination and related approvals.
• Extension and trust amendments: On February 13, 2026, an Extension EGM approved amendments to provide an extended timeline for completing the business combination, including up to a 12-month extension window to February 18, 2027, with extension deposits into the Trust Account and related loan mechanics. The Trust Agreement was amended to commence liquidation of the Trust Account after applicable instructions for closing or failure to complete an initial business combination.
• Redemptions and extensions: Following the Extension EGM, ordinary shares were redeemed in connection with the extension. Additional deposits to the Trust Account were made to extend the period to complete the initial business combination, including a $690,000 deposit around November 17, 2025, and $50,000 deposits on February 18, 2026 and March 13, 2026, with corresponding unsecured promissory notes issued.

Post-transaction considerations and regulatory context

• The Company identifies regulatory considerations related to PRC operations and the potential for the combined company to be affected by PRC regulatory rules if the target is China-based.
• The Company discusses risks related to foreign ownership, CFIUS considerations for U.S. target transactions, and the potential impact of PRC regulatory actions on the ability to consummate a business combination or list on U.S. exchanges.
• The Company has assets and operations outside the United States, including in China, and acknowledges potential enforcement and cross-border legal considerations, including potential limitations on access to U.S. capital markets if regulatory actions restrict the PCAOB-inspected auditor framework (HFCAA considerations).

Headquarters

• Principal executive office: 1412 Broadway, 21st Floor, Suite 21V, New York, NY 10018

Key quantitative details

• Units issued at IPO: 6,000,000 Units
• Public proceeds in trust: $69,000,000
• Private Units sold: 200,000 Private Units (Sponsor) + 13,500 Additional Private Units (Sponsor)
• Gross proceeds from private placements: $2,000,000 + $135,000
• Over-Allotment Units: 900,000 Units (exercised in full)
• Representative Shares: 241,500 ordinary shares
• Employees: 2 executive officers (CEO and CFO)
• Revenue: None to date
• Current focus: Sourcing and evaluating business combination targets; potential SL Bio transaction described above
• Assets in Trust: $69,000,000
• Post-transaction plan: PubCo Ordinary Shares to be listed on Nasdaq after the SL Bio Business Combination closing