The determination of the Inheritance Tax or Gift Tax is only to be desisted if the amount of tax equals at least EUR 10 and the tax became chargeable before January 1, 2017. In regard to acquisitions after December 31, 2016 the determination of the Inheritance Tax or Gift Tax is only to be desisted if the amount of tax supersedes EUR 10 in favor or EUR 25 at the expense of the tax payer.
For more details regarding the de minimis limit see Koeniger, The German Inheritance and Gift Tax, 2017, p. 281.