Forge Nano Holdings, Inc.

On April 20, 2026, Archimedes Tech SPAC Partners II Co., a Cayman Islands exempted company (“ATII”), entered into that certain Agreement and Plan of Merger (the “Merger Agreement”), by and among ATII, ATII Holdings Inc., a Delaware corporation and a wholly-owned subsidiary of ATII (“Pubco”), ATII Merger Sub Inc., a Delaware corporation and a wholly-owned subsidiary of ATII (“Merger Sub I”), ATII Merger Sub II, LLC, a Delaware limited liability company and a wholly-owned subsidiary of ATII (“Merger Sub II”), and Forge Nano, Inc., a Delaware corporation (“Forge Nano”).

At the extraordinary general meeting of ATII held on October 16, 2026 (the “Extraordinary General Meeting”), the holders of ATII Ordinary Shares (as defined below) approved the Business Combination (as defined below) and the other proposals described in the definitive proxy statement/prospectus, dated September 22, 2026 (the “Proxy Statement/Prospectus”), filed with the U.S. Securities and Exchange Commission (the “SEC”) on September 24, 2026, which forms a part of the registration statement on Form S-4 (File No. 333-295563) under the Securities Act of 1933, as amended (the “Securities Act”), initially filed with the SEC on May 5, 2026 and declared effective by the SEC on September 22, 2026.

As described in more detail below, on October 21, 2026, ATII consummated the Domestication Merger (as defined below) and, on October 22, 2026 (the “Closing Date”), the parties to the Merger Agreement consummated the Company Mergers (as defined below) and the other transactions contemplated by the Merger Agreement (the “Closing”).

Unless context otherwise requires, “we,” “us,” “our” and the “Company” refer to Forge Nano Holdings, Inc. (formerly known as ATII Holdings Inc.) and its consolidated subsidiaries after giving effect to the Business Combination, and “Pubco” refers to such entity prior to giving effect to the Business Combination. Capitalized terms used but not defined in this Current Report on Form 8-K (this “Report”) have the meanings given to them in the Proxy Statement/Prospectus, and such definitions are incorporated herein by reference.

Domestication Merger

Pursuant to the Merger Agreement and as described in the section titled “Proposal No. 1 – The Business Combination Proposal” beginning on page 140 of the Proxy Statement/Prospectus, on October 21, 2026, ATII re-domiciled and became a Delaware corporation by merging with and into Pubco (the “Domestication Merger”), following which the separate corporate existence of ATII ceased and Pubco continued as the surviving corporation. At the effective time of the Domestication Merger (the “Domestication Merger Effective Time”), Pubco adopted Delaware organizational documents (the Charter and the Bylaws, each as defined in Item 5.03 below), which provide, among other things, that the name of Pubco was changed to “Forge Nano Holdings, Inc.”

Immediately prior to the Domestication Merger Effective Time, each then issued and outstanding unit of ATII (an “ATII Unit”) separated and converted automatically into one ordinary share, par value $0.0001 per share, of ATII (an “ATII Ordinary Share”) and one-half of one warrant of ATII, each whole warrant entitling the holder thereof to acquire one ATII Ordinary Share at a purchase price of $11.50 per share (the “ATII Warrants”), and all ATII Units ceased to be outstanding and ceased to exist. At the Domestication Merger Effective Time, each then issued and outstanding ATII Ordinary Share was cancelled in exchange for the right to receive one share of common stock, par value $0.0001 per share, of Pubco (each, a share of “Pubco Common Stock”) and each whole ATII Warrant that was outstanding and unexercised converted automatically into a warrant to acquire one share of Pubco Common Stock at a purchase price of $11.50 per share (each, a “Pubco SPAC Warrant”), pursuant to the terms of the Warrant Agreement, dated as of February 10, 2025 (as assumed by Pubco pursuant to the Assumption of Warrant Agreement dated as of October 21, 2026, the “ATII Warrant Agreement”), by and between ATII and Odyssey Transfer and Trust Company, as warrant agent.