--- title: "SL Science Holding files F-4 for Horizon Space Acquisition II and SL BIO merger" url: "https://aibio.space/news/sl-science-holding-files-f-4-horizon-space-acquisition-ii-sl-bio/" publisher: "aibio.space (Biotech Investor Relations News)" date: "2025-12-18" section: "Mergers" tickers: "NASDAQ:SLBT" source: "https://www.sec.gov/Archives/edgar/data/2070534/000121390025122905/ea0242738-07.htm" summary: "SL Science Holding's F-4 says the blank-check company's trust holds $69,000,000 and that its chairman would control about 58% of the voting power of the co" --- By the aibio.space news desk. Sources - [SL Science Holding Limited F-4 (2025-12-18)](https://www.sec.gov/Archives/edgar/data/2070534/000121390025122905/ea0242738-07.htm) - [ea0273011-04.htm](https://www.sec.gov/Archives/edgar/data/2070534/000121390026004683/ea0273011-04.htm) - [ea027466602-425_slscience.htm](https://www.sec.gov/Archives/edgar/data/2070534/000121390026009873/ea027466602-425_slscience.htm) [SLBT](https://aibio.space/companies/sl-science/) 2025-12-18 # SL Science Holding files F-4 for Horizon Space Acquisition II and SL BIO merger Tickers [SLBT](https://aibio.space/companies/sl-science/) SL Science Holding's F-4 says the blank-check company's trust holds $69,000,000 and that its chairman would control about 58% of the voting power of the combined company. The target's main products include cancer drugs that the filing does not show as approved. ## Key facts - **Company**: SL Science Holding Limited (NASDAQ: SLBT) - **News type**: Mergers - **Primary source**: [SL Science Holding Limited F-4 (2025-12-18)](https://www.sec.gov/Archives/edgar/data/2070534/000121390025122905/ea0242738-07.htm) *A conference room set for a meeting. CC0, via rawpixel. The picture shows the field, not the companies named.* SL Science Holding Limited filed a registration statement on Form F-4 with the Securities and Exchange Commission on December 18, 2025. The document is a preliminary proxy statement and prospectus dated December 17, 2025, for a shareholder vote at Horizon Space Acquisition II Corp., a blank-check company known as HSPT, on its business combination with SL BIO Ltd., through a new Cayman Islands holding company called PubCo. The two companies signed the business combination agreement on May 9, 2025. The meeting date is still blank in the filing. ## The terms Each HSPT ordinary share outstanding before the first merger is cancelled for the right to receive one new PubCo ordinary share, and each HSPT right first converts into one-tenth of an HSPT ordinary share. SL BIO shareholders receive PubCo shares under an exchange ratio equal to $5.568 billion divided by $10.00 per share, divided by the number of SL BIO ordinary shares outstanding just before the second merger. PubCo will apply to list its ordinary shares on the Nasdaq Global Market under the symbol SLBT. HSPT has until February 18, 2026 to complete a deal, or May 18, 2026 if fully extended. ## What the SPAC holds A total of $69,000,000 from HSPT's initial public offering, its private placements and the over-allotment option was placed in a trust account with Wilmington Trust, N.A. as trustee. Maxim Group LLC, the underwriters' representative, exercised the over-allotment option in full in November 2024 for 900,000 units and $9,000,000 of gross proceeds. Public shareholders can redeem for their part of the trust before the vote, though no holder or group may redeem more than 15%. Cash that leaves the trust through redemptions is not available to the combined company. The filing says HSPT has no revenue and has had losses since inception. A $690,000 payment that extended its deadline from November 18, 2025 to February 18, 2026 was made by Hsiao-Lan Wu, a third party to the sponsor. The sponsor, Horizon Space Acquisition II Sponsor Corp., would receive 1,655,000 PubCo shares for founder shares it bought for $23,985, and 234,850 PubCo shares for private shares it bought for $2,135,000. The filing says the sponsor would hold less than 1% of the voting power after closing. ## Control of the combined company Mr. William Wang, SL BIO's chief executive officer and chairman, is expected to beneficially hold approximately 58% of the voting power of PubCo after closing. The filing says PubCo would be a controlled company under Nasdaq listing rules, and may therefore be exempt from certain corporate governance requirements. ## The target business SL BIO operates in Taiwan through SL Bio Co., Ltd. The filing says the holding company does not operate through variable interest entities and has no subsidiaries in mainland China. It lists SL BIO's main products as exosome-related products, GDT new drugs for brain cancer and pancreatic cancer, and a new drug, CD19 (Arm T), for blood cancer. The filing does not present these as approved products. The risk section says cell therapy products are a novel approach that creates significant challenges and uncertainty, and that exosome products will likely face heightened FDA scrutiny. ## The fairness opinion and advisers HSPT's board obtained a fairness opinion dated May 5, 2025 from King Kee Appraisal and Advisory Limited, known as KKG. KKG used a discounted cash flow method and a comparable public companies method, with SL BIO management's projections for 2025 to 2034 and a 2% growth rate from 2035. The filing says the HSPT board did not rely on those projections in recommending the deal, and that the opinion will not reflect changes in circumstances before completion. The F-4 cover lists Robinson & Cole LLP and VCL Law LLP for copies of communications, without saying which firm represents which party. ## What the filing leaves open The filing is preliminary. The proposals are cross-conditioned, so if any one is not approved, the business combination cannot close. [Report an error](https://aibio.space/reputation/#correction) ## Companies in this story SLBT SL Science Holding Limited NASDAQ ยท Taiwan Open the starter desk ## More in Mergers Mergers ### [InMed sets November 5 record date for CVRs tied to Mentari merger](https://aibio.space/news/inmed-sets-november-5-record-date-cvrs-tied-mentari-merger/) Oct 27, 2026 Mergers ### [Rallybio declares estimated $82.7 million cash distribution tied to Avenzo merger](https://aibio.space/news/rallybio-declares-estimated-82-7-million-cash-distribution-tied-avenzo/) Oct 26, 2026 Mergers ### [Skye Bioscience files preliminary proxy for its Redx Pharma acquisition](https://aibio.space/news/skye-bioscience-files-preliminary-proxy-redx-pharma-acquisition/) Oct 26, 2026 --- Source page: https://aibio.space/news/sl-science-holding-files-f-4-horizon-space-acquisition-ii-sl-bio/. Facts in aibio.space stories are checked against company filings and releases; opinion is labelled. Cite as: aibio.space, "SL Science Holding files F-4 for Horizon Space Acquisition II and SL BIO merger", 2025-12-18, https://aibio.space/news/sl-science-holding-files-f-4-horizon-space-acquisition-ii-sl-bio/