Receipt of the warning letter by the addressee does not have to be proven
Proof of receipt of a warning letter is not a prerequisite for its effectiveness, as effective legal protection can only be achieved if action is taken quickly. The basic possibility of sending a registered letter does not change this.
Dispensability of a warning if it is clear that it will be unsuccessful
The out-of-court warning is merely an obligation with regard to the reimbursement of legal costs, but not a prerequisite for admissibility in court proceedings. The warning is even dispensable if it is foreseeable that it will be unsuccessful or if it is unreasonable for other reasons. However, a deliberately negligent or intentional breach of competition law alone is not sufficient for this without additional circumstances.
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