The formulation is not so easy to read (very common for German laws), but it includes also the regulations for normal coins:
"Erfolgt eine einzelne Zahlung sowohl in Euro-Münzen als auch in deutschen Euro-Gedenkmünzen, ist niemand verpflichtet, mehr als 50 Münzen anzunehmen; dies gilt auch dann, wenn der Gesamtbetrag 200 Euro unterschreitet."
"If a single payment is made using both euro coins and German commemorative euro coins, no one is obliged to accept more than 50 coins; this also applies if the total amount is less than 200 euros."
So, there exist two cases in which the vendor is not obliged to take more than 50 coins:
- The payment consists of both normal Euro coins and German commemorative euro coins
- The payment is less than EUR 200.
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Independently, there does exist another source of law by which the vendor is not obliged to take more than 50 coins: Artikel 11 der EG-Verordnung Nr. 974/98 des Rates über die Einführung des Euro, EU-Amtsblatt L139 vom 11. Mai 1998:
> https://eur-lex.europa.eu/legal-content/DE/TXT/PDF/?uri=CELE... (German)
> https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELE... (English)
"As from 1 January 2002, the participating Member States shall issue coins denominated in euro or in cent and complying with the denominations and technical specifications which the Council may lay down in accordance with the second sentence of Article 105a(2) of the Treaty. Without prejudice to Article 15, these coins shall be the only coins which have the status of legal tender in all these Member States. Except for the issuing authority and for those persons specifically designated by the national legislation of the issuing Member State, no party shall be obliged to accept more than 50 coins in any single payment."
Relevant part of this article:
"Except for the issuing authority and for those persons specifically designated by the national legislation of the issuing Member State, no party shall be obliged to accept more than 50 coins in any single payment."