I have already dealt with the topic of abusive cease-and-desist letters here on the blog a few times, and the basic questions have actually been clarified in literature and case law.

In a ruling that has now become known, the Federal Court of Justice has finally confirmed the essentials. Thus, the latter decided as follows:

a) Abusive prosecution within the meaning of Sec. 8 para. 4 sentence 1 UWG exists in principle if a large number of warning notices are associated with a prosecution expense that threatens the existence of the person issuing the warning notice in relation to his annual profit, and the person issuing the warning notice has an interest in the prosecution.
there is no significant economic interest in the legal prosecution.

b) In the overall consideration of the relevant circumstances required for the examination of an abusive prosecution by means of mass warnings against dealers, it may have to be taken into account that the person issuing the warning notice, because of the
advertising statements has already obtained an injunction against the manufacturer.

c) If there is a lack of any economically significant interest in the legal prosecution, the indicative effect of a very extensive warning activity in relation to the commercial activity for an abuse of rights does not cease to exist due to the fact that the person issuing the warning has previously endeavored to simply and inexpensively
shut down.

However, it remains to be seen whether this decision will really stem the tide of cease-and-desist letters and put the actually good and clever means of cease-and-desist letters in a better light again.

The reason for this is that the question of whether a warning is abusive is ultimately a question of a judicial determination. So, if one has the indications of a possible abuse of rights, which is already not self-evident, one must also defend this opinion in court, and since it would be an objection, for example, in the context of injunction proceedings, one must also prove the circumstances. Of course, this involves a certain cost risk that not all clients want to take on.

The advantage, if you can call it that, is that any damage caused by a warning or by an injunction can of course be claimed against the plaintiff.