In C-529/16 the Munich Fiscal Court had asked the European Court of Justice (ECJ) whether the customs valuation provisions of the Community Customs Code (CCC) in force at the time of the events permit an agreed transfer price, which is composed of an amount initially invoiced and declared, and a flat-rate adjustment made after the end of the accounting period using an allocation key, regardless of whether a subsequent debit charge or credit is made to the declarant at the end of the accounting period, and if so, whether the customs value may be reviewed and/or determined using simplified approaches where the effects of subsequent transfer pricing adjustments (both upward and downward) can be recognised. The ECJ ruled that these provisions do not permit an agreed transaction value, composed of an amount initially invoiced and declared and a flat-rate adjustment made after the end of the accounting period, to form the basis for the customs value, without it being possible to know at the end of the accounting period whether that adjustment would be made up or down. Subsequently, the case was referred to the German Federal Fiscal Court (Bundesfinanzhof – BFH) which in its judgment (Judgment of 17 May 2022, VII R 2/19, available in English under https://tpcases.com/wpcontent/ uploads/VII-R-2-19-ENG-NW-1.htm; this article partially uses a translation made by the authors where it seemed more appropriate or better understandable) rejected the flat rate adjustment, primarily with the arguments that such additions or deductions of the customs value were not quantifiable at the time of the acceptance of the customs declaration, and that a refund based on circumstances occurring after that time is not permitted under the EU customs legislation. As the underlying issues are widely debated among practitioners (see, inter alia, https://www.pwc.nl/ en/insights-and-publications/services-and-industries/tax/the-impact-of-hamamatsu-under-the-union-customs-code.html, https://wts.com/global/pub lishing-article/20221102-appeal-in-hamamatsu-case-rejected-by-german-federal-court~publishing-article?language=en; https://www.internatio naltradecomplianceupdate.com/2022/10/13/the-hamamatsu-tp-customs-valuation-case-comes-to-a-surprising-conclusion; Friedhoff & Schippers, ECJ Judgment in Hamamatsu Case: An Abrupt End to Interaction Between Transfer Pricing and Customs Valuation?, EC TAX REVIEW 2019-1, https://pure.eur.nl/ws/portalfiles/portal/48111114/114141.pdf; Roth/Rinnert, Zur Berücksichtigung von Verrechnungspreisen bei der Zollwertermittlung, Deutsches Steuerrecht 2018, 2090; Rinnert, Anmerkung zum EuGH-Urteil vom 20 December 2017 C-529/16, ZfZ 2018, 68; Rinnert, Zollwert und Verrechnungspreise, AW-Prax 2022, 570: Krüger, Anmerkung zu BFH, Urteil vom 17 May 2022, VII R 2/19, ZfZ 2022, 367 (372)) it is worthwhile to report and analyse the proceedings and this judgment. In order to facilitate the understanding of the various judgments in the context of the currently applicable Union Customs Code (UCC), its Delegated (UCC-DA) and Implementing Act (UCC-IA), the corresponding Articles now in force have been added in square brackets.