Table of Contents As filed with the U.S. Securities and Exchange Commission on November 25, 2025 Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 TERRESTRIAL ENERGY INC. (Exact name of registrant as specified in its charter) Delaware 3443 98-1785406 (Primary Standard Industrial (I.R.S. Employer Identification Number) Charlotte, NC 28217 (646) 687-8212 (Address, including zip code, and telephone numb ...

Core Viewpoint - Terrestrial Energy Inc. is advancing its Generation IV nuclear power plants, specifically the Integral Molten Salt Reactor (IMSR), which aims to provide low-cost, reliable, and clean energy solutions while participating in upcoming investor conferences to engage with stakeholders [1][2]. Company Overview - Terrestrial Energy is focused on developing small modular nuclear plants utilizing proprietary IMSR technology, which enhances capital efficiency, cost reduction, and versatility in energy supply [2]. - The IMSR is designed for dual-use applications, providing both industrial heat and electricity, and is applicable in sectors such as petrochemicals and data centers, thereby broadening the scope of nuclear energy beyond traditional electric power markets [2]. - The company is actively collaborating with regulators, suppliers, and industrial partners to build and license the first IMSR plants, targeting deployment in the early 2030s [2]. Upcoming Events - The company will participate in the B. Riley Securities Convergence Conference on December 4, 2025, in New York City, and the 2nd Annual Craig-Hallum Nuclear Energy Forum on December 11, 2025, which will be held virtually [5].

As filed with the Securities and Exchange Commission on November 24, 2025 Registration No. 333-291343 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 _________________________ AMENDMENT NO. 1 TO FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 _________________________ HCM IV Acquisition Corp. (Exact name of registrant as specified in its charter) _________________________ Cayman Islands 6770 98-1883478 (State or other jurisdiction of incorporation or organization) (P ...

Core Insights - Terrestrial Energy Inc. (NASDAQ:IMSR) has recently started trading on NASDAQ, focusing on the development of molten salt nuclear reactors, which are believed to have a shorter delivery timeline compared to traditional nuclear alternatives [2] - Jim Cramer has expressed skepticism about the nuclear power sector, noting that many companies in this field have long delivery timelines, while he has favored GE Vernovaas as a top nuclear stock pick [2][3] - Cramer hopes that Terrestrial Energy Inc. performs better than other nuclear companies, drawing parallels to the year 2000, indicating a cautious outlook on the nuclear industry [3] Company Overview - Terrestrial Energy Inc. is engaged in the development of molten salt nuclear reactors, which are positioned as a more efficient alternative in terms of delivery timelines [2] - The company recently rang the opening bell on NASDAQ, marking its entry into the public market [2] Market Context - The nuclear power industry is currently viewed with skepticism, with Cramer highlighting the challenges faced by many companies in this sector [3] - There is a contrasting view that AI stocks may offer better investment opportunities with higher returns and limited downside risk compared to nuclear stocks [3]

Core Viewpoint - Terrestrial Energy Inc. has appointed Jim Howe and David O'Keefe to enhance its leadership team and accelerate the deployment of its Integral Molten Salt Reactor (IMSR) technology across various market sectors [1][5]. Company Developments - The appointments of Howe and O'Keefe are aimed at strengthening the company's government relations and project management capabilities, which are critical for capturing the growing market demand for clean energy solutions [2][5]. - Jim Howe, with extensive experience in government relations, will focus on federal and state engagements, particularly in Texas, to support the commercial IMSR plant project at Texas A&M University [3][5]. - David O'Keefe, with a strong background in business development and finance, will oversee the commercial delivery of the RELLIS project and expand the company's IMSR deployment opportunities in the U.S. [4][5]. Market Position and Strategy - Terrestrial Energy's IMSR plant is designed to provide clean, reliable, and cost-effective energy for industrial operations, data centers, and power grids, addressing the rising market demand for scalable energy solutions [2][8]. - The company is aligned with federal policies aimed at accelerating the deployment of advanced nuclear technologies, targeting a nuclear generation capacity of 400 GW by 2050 [6]. - Recent milestones include the selection of a commercial IMSR plant site at Texas A&M's RELLIS campus and participation in various Department of Energy programs, which validate the company's strategies and enhance its market position [7][6]. Future Outlook - The leadership appointments and recent achievements position Terrestrial Energy at the forefront of the U.S. nuclear energy renaissance, with plans to build and commission the first IMSR plants in the early 2030s [8][6].

As filed with the Securities and Exchange Commission on November 6, 2025 Registration No. UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 _________________________ FORM S-1 REGISTRATION STATEMENT THE SECURITIES ACT OF 1933 _________________________ HCM IV Acquisition Corp. (Exact name of registrant as specified in its charter) _________________________ | Cayman Islands | 6770 | 98-1883478 | | --- | --- | --- | | (State or other jurisdiction of | (Primary Standard Industrial | (I.R.S. ...

Core Insights - Terrestrial Energy has appointed Sarfraz M. Taj as Vice President of Business Development, bringing over 20 years of nuclear industry experience from Constellation Energy [1][2] - The company aims to accelerate the commercialization of its Integral Molten Salt Reactor (IMSR) technology following its public listing [1][3] Company Developments - Sarfraz Taj's role will focus on expanding strategic partnerships and customer relationships, both in the U.S. and globally [2] - His previous experience includes significant contributions to major strategic transactions and initiatives in new nuclear development and advanced clean technologies at Constellation Energy [2] - Terrestrial Energy has made several key appointments recently, including David O'Keefe as Vice President of Business Development and Project Management, who has over 25 years of experience in the energy sector [3] Technology and Market Position - The IMSR technology is positioned as a future solution for clean, reliable, and cost-competitive nuclear power, utilizing Standard Assay Low-Enriched Uranium fuel and a capital-efficient business model [3][4] - IMSR plants are designed for distributed supply of low-cost, reliable, and clean energy, extending the application of nuclear energy beyond traditional electric power markets [4] - The company is engaged with regulators and industrial partners to build and license the first IMSR plants in the early 2030s, supporting global decarbonization efforts [4]

Core Insights - Terrestrial Energy has commenced trading on Nasdaq under the ticker symbol "IMSR" following its business combination with HCM II Acquisition Corp, which was completed on October 28, 2025 [1][2] - The company secured over $292 million in gross transaction proceeds to support its business plan and accelerate technology commercialization [1][2] - Terrestrial Energy's Integral Molten Salt Reactor (IMSR) technology aims to provide low-cost, high-temperature, clean, and flexible heat and electricity, enhancing economic efficiency and time-to-market [1][3] Financial Highlights - The business combination resulted in gross proceeds exceeding $292 million, including $50 million from a common stock PIPE and approximately $242 million from HCM II's trust account, with redemptions of less than 1% of HCM II shares [2] Technology and Innovation - The IMSR technology is a Generation IV nuclear technology designed for high capital efficiency and low-cost industrial heat and electric power, addressing the urgent global energy demands [3][4] - The IMSR plant design has a capacity of 822 MWth / 390 MWe, utilizing Standard-Assay Low Enriched Uranium (SALEU) fuel [4][6] Strategic Partnerships - Terrestrial Energy has established key partnerships with institutions such as Texas A&M University, the U.S. Department of Energy, and several national laboratories, enhancing its capabilities in technology development and regulatory engagement [5][6] Market Positioning - The company aims to extend the application of nuclear energy beyond traditional electric power markets, targeting critical applications in various industries, including data centers and industrial processes [4][7] - Terrestrial Energy is positioned to capitalize on the increasing demand for low-cost, clean, and reliable energy solutions, contributing to global decarbonization efforts [7]

Core Viewpoint - Terrestrial Energy has completed its business combination with HCM II Acquisition Corp, resulting in over $292 million in gross proceeds to accelerate the deployment of its Integral Molten Salt Reactor (IMSR) nuclear technology, with trading set to begin on Nasdaq under the ticker symbol "IMSR" on October 29, 2025 [1][2][11] Company Overview - Terrestrial Energy is focused on developing Generation IV nuclear plants utilizing proprietary IMSR technology, which offers innovations in affordability, efficiency, and versatility for nuclear energy supply [5][13] - The IMSR plants are designed to provide zero-carbon, clean, firm, low-cost, high-temperature industrial heat and electricity, suitable for various industrial applications including data centers and green fuels [6][13] Technology and Market Position - The IMSR technology is differentiated from traditional nuclear technologies by its use of molten salt reactor design, which enhances efficiency and safety [6][7] - The plants will utilize Standard-Assay Low Enriched Uranium (SALEU) fuel, providing a secure and scalable fuel supply chain, which is strategically advantageous given geopolitical challenges affecting High-Assay Low-Enriched Uranium (HALEU) availability [7] Strategic Partnerships and Development - Terrestrial Energy has established partnerships with notable organizations such as Westinghouse and the U.S. Department of Energy, and has been selected for key government programs to accelerate commercialization [8][10] - A significant partnership with Texas A&M University aims to site a commercial IMSR plant, showcasing the technology and benefiting from the university's leadership in nuclear research [9] Financial Overview - The business combination has resulted in gross proceeds exceeding $292 million, including a $50 million PIPE investment and approximately $242 million from HCM II's trust account, with minimal shareholder redemptions [11]

Core Points - HCM II Acquisition Corp. has received shareholder approval for its business combination with Terrestrial Energy Inc., a developer of small modular Generation IV nuclear plants utilizing proprietary Integral Molten Salt Reactor (IMSR) technology [1][2] - The closing of the business combination is anticipated on or about October 27, 2025, with trading on Nasdaq commencing on October 28, 2025, under the symbols "IMSR" and "IMSRW" [2] Company Overview - Terrestrial Energy focuses on developing Generation IV nuclear plants that leverage IMSR technology, which offers benefits in capital efficiency, cost reduction, and versatility for various industrial applications [3] - The IMSR plants are designed to provide low-cost, reliable, and clean energy, extending the application of nuclear energy beyond traditional electric power markets [3] - The company aims to support energy demand growth and decarbonization efforts, with plans to license and commission the first IMSR plants for operation in the early 2030s [3] HCM II Acquisition Corp. Overview - HCM II is a special-purpose acquisition company (SPAC) formed to pursue business combinations with established companies poised for growth [4] - The management team includes Shawn Matthews as Chairman and CEO, and Steven Bischoff as President and CFO [5]