In Germany, a company may call a consumer for advertising only if the consumer has agreed in advance. The rule is Section 7 of the Act Against Unfair Competition. The Federal Network Agency explains it on its website. Jeder, der Sie zu Werbezwecken anrufen möchte, muss zuvor Ihre ausdrückliche Einwilligung einholen. Anyone who wants to call you for advertising must first obtain your express consent. The company must record the consent at once and in detail, and it must show the record to the agency on request. Fines can reach 300,000 euros. A consumer does not have to say no to such a call. Without an earlier yes, the call is already unlawful.