Contract analysis

I. Purpose and Authorization Calderwood & Harkness LLP ("C&H" or the "Firm") respectfully submits this letter and the accompanying enclosed materials on behalf of our client, Halcyon Semiconductor Inc. ("HSI"), a corporation organized under the laws of the State of Delaware (EIN: 84-2917630), and HSI's parent company, Halcyon Semiconductor AG ("HSAG"), an Aktiengesellschaft organized and existing under the laws of th

II. Description of the Application By this submission, HSI formally files an application for a bilateral Advance Pricing Agreement pursuant to Revenue Procedure 2015-41, 2015-35 I.R.B. 263, as modified and supplemented (the "Revenue Procedure"). This application requests that the United States competent authority, acting through the Advance Pricing and Mutual Agreement Program of the Large Business & International Di

III. Covered Transactions The APA application identifies three principal categories of controlled transactions between HSAG and HSI that are the subject of this bilateral APA request. Each category of transaction is described below, together with a summary of the applicable intercompany agreements and the most recently available financial data for fiscal year 2024. A. Tangible Goods — Wafer and Die Sales HSAG manufac

IV. Proposed Transfer Pricing Methods The APA application sets forth proposed transfer pricing methods for each of the three categories of covered transactions, as summarized below. Full detail is provided in the enclosed APA Application Supporting Narrative (Enclosure 2), Economic Analysis Appendix (Enclosure 3), and Legal Analysis Memorandum (Enclosure 4). A. Tangible Goods (Wafer/Die Sales) — TNMM / CPM For the in

V. Proposed APA Term and Rollback Request The application proposes the following temporal scope for the bilateral APA: Prospective APA Term: Five (5) tax years — January 1, 2025, through December 31, 2029. Rollback Request: Three (3) prior tax years — January 1, 2022, through December 31, 2024. Total Covered Period (if rollback is granted): Eight (8) tax years — January 1, 2022, through December 31, 2029. Both HSI an

VI. Pre-Filing Conference Prior to the submission of this formal APA application, a pre-filing memorandum was submitted anonymously to the IRS APMA on April 14, 2025, in accordance with Section 4 of the Revenue Procedure. A pre-filing conference was subsequently held on May 19, 2025, at the IRS offices in Washington, D.C. Representatives of the APMA program participated in the conference, which addressed the proposed

VII. German Competent Authority Coordination Consistent with the bilateral nature of this APA request, a parallel German APA application package is being prepared by HSAG's German tax counsel, Kettner Pflüger Rechtsanwälte (Dr. Tobias Kettner, Partner, Tax; Bockenheimer Landstraße 72, 60323 Frankfurt am Main, Germany), for submission to the Bundeszentralamt für Steuern ("BZSt") in Bonn, Germany. The German applicatio

VIII. Enclosures The following materials are enclosed with this letter and collectively constitute the APA application submitted on behalf of HSI:

1. IRS Form 14661 — Completed APA Application Form for Halcyon Semiconductor Inc. (EIN: 84-2917630) and Halcyon Semiconductor AG (Steuernummer: 203/118/04527), executed by an authorized officer of HSI.

2. APA Application Supporting Narrative — Comprehensive description of the applicants (HSI and HSAG), their business operations and organizational structure, the covered controlled transactions, the proposed transfer pricing methods for each category of transaction, the proposed APA term, and the rollback request. The narrative addresses each of the items specified in Section 6 of Rev. Proc. 2015-41.

3. Economic Analysis Appendix — Detailed benchmarking studies, including the CPM/TNMM analysis for the tangible goods transactions, the CUT analysis and corroborative residual profit split analysis for the royalty transactions, and the income-method anticipated benefit share analysis for the cost-sharing arrangement. The appendix includes full documentation of comparability adjustments, search strategies, database pa

4. Legal Analysis Memorandum — Analysis of the legal basis for the proposed transfer pricing methods under IRC § 482, Treasury Regulations §§ 1.482-1 through 1.482-9, the OECD Transfer Pricing Guidelines for Multinational Enterprises and Tax Administrations (2022 ed.), and Articles 9 (Associated Enterprises) and 25 (Mutual Agreement Procedure) of the US-Germany Income Tax Treaty. The memorandum also addresses the pen

5. Financial Data Appendix — Segmented financial data for HSI and HSAG, intercompany transaction schedules, and reconciliations to audited consolidated financial statements for fiscal years 2020 through 2024. Financial statements have been audited by Gresham Whitfield LLP, independent registered public accounting firm. Key financial data points for FY 2024 are summarized as follows: Halcyon Semiconductor Inc. (HSI) —

6. IRS Form 2848 — Power of Attorney and Declaration of Representative — Authorizing Leonard Cross, Sylvia Hartwell, and Leila Nazari of Calderwood & Harkness LLP to represent HSI before the IRS for tax years 2022 through 2029 with respect to IRC § 482 transfer pricing matters. Executed by an authorized officer of HSI.

7. User Fee Payment — Check No. 108427, dated July 7, 2025, in the amount of $113,500.00, payable to the order of the United States Treasury, representing the applicable large-case APA user fee for bilateral applications as of the date of this submission, in accordance with Section 4.12 of Rev. Proc. 2015-41 (as updated by subsequent guidance).

IX. Applicable Legal Authorities The APA application is submitted in reliance upon, and the proposed transfer pricing methods are consistent with, the following legal authorities: • Internal Revenue Code §§ 482, 6662(e), and 6662(h) • Treasury Regulations §§ 1.482-1 through 1.482-9 • Treasury Regulation § 1.6662-6 • Revenue Procedure 2015-41, 2015-35 I.R.B. 263 • OECD Transfer Pricing Guidelines for Multinational Ent

X. Contact Information and Availability All communications relating to this APA application should be directed to: Leonard Cross Partner, Tax Calderwood & Harkness LLP 599 Lexington Avenue, 38th Floor New York, New York 10022 Telephone: (212) 848-6247 Email: leonard.cross@calderwoodharkness.com Mr. Cross, together with Sylvia Hartwell and Leila Nazari, are available to meet with the APMA team at the program's earlies

XI. Closing We express our sincere appreciation for the APMA program's consideration of this bilateral APA application. HSI and HSAG are firmly committed to a cooperative and transparent bilateral process and recognize the significant benefits that the APA program provides to taxpayers and tax administrations alike in achieving certainty and preventing double taxation. HSI and HSAG will fully comply with all informat