In its ‘Quelle’ judgment, the German Federal Court of Justice addressed the issue how national law can be interpreted and methodically developed in conformity with European directives. Most notably in its second headnote, the Court defines the requirements for a purpose-oriented reduction (teleologische Reduktion) as tool for the methodical development of law. The case concerns the sale of consumer goods (Section 474 (1), sentence 1, of the Civil Code). It deals with the issue, whether – according to Section 439 (4) of the Civil Code (Section 439 (5) of the Civil Code since 1 January 2018) and Section 346 (1) of the Civil Code – a seller delivering a replacement may require the purchaser to surrender any benefits received, or to receive compensation for the use of the defective goods.
The European Court of Justice was asked for preliminary ruling on the question, whether the seller was enjoined from claiming any such rights due to Article 3 (2) in conjunction with Article 3 (3), sentence 1, and Article 3 (4) or Article 3 (3), sentence 3, of Directive 1999/44/EG of the European Parliament and of the Council of 25 May 1999 on certain aspects of the sale of consumer goods and associated guarantees (OJ L 171, 07/07/1999, p. 12).
The European Court of Justice positively confirmed this question. Accordingly, the German Federal Court of Justice concluded, that – due to the principle of conformity with European law – Section 439 (4) of the Civil Code (or Section 439 (5) of the Civil Code since 1.1.2018) must be interpreted restrictively. Just a month after the pronouncement of judgment, the German lawmaker rendered the relevant paragraphs of the BGB accordingly. Now Section 474 (2) of the Civil Code (now Section 475 (3) of the Civil Code), contain no right to claim back benefits received, or receive compensation for the use of the defective goods in case of replacement in consumer sales.
On the Quelle-case see also M?llers, Juristische Methodenlehre, 2nd ed., Munich 2019, § 12 mn. 58 et seqq., 62, 69, 71, 74, 110. Generally, on the methodology of European Law see M?llers, Juristische Methodenlehre, 2nd ed., Munich 2019, § 12.

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