Definition and function of the secondary burden of proof The secondary burden of proof is a procedural legal concept in German civil procedure law. It comes into play when a party in a legal dispute is unable to fully prove all the facts in its favor because it lacks or does not have access to the necessary information. In such cases, the other party is obliged to provide more detailed information on the facts that lie within its sphere of influence as far as possible. The secondary burden of proof therefore supplements the general burden of proof and serves to ensure equal opportunities for the parties in the process.

Differentiation from the burden of proof While the burden of proof determines which party must prove a fact if it is disputed, the secondary burden of proof obliges the other party to substantiate or explain facts to which only they have access. It therefore does not lead to a reversal of the burden of proof, but merely supplements it by establishing a procedural obligation to cooperate for the party who has the relevant information advantage.

Requirements of the secondary burden of proof Certain requirements must be met for a secondary burden of proof to exist:

• The party with the primary burden of proof must have exhausted all available means of discovery.
• The opposing party must have exclusive knowledge or information that is necessary to clarify the facts of the case.
• The facts that are to be substantiated must typically be in the sphere of the opposing party.

Only if these requirements are met does the other party have a secondary burden of proof.

Legal consequences of a breach of the secondary burden of proof If the party on whom a secondary burden of proof has been imposed fails to comply with this obligation, this can lead to a reduction in the burden of proof for the party obliged to provide evidence during the trial. Although there is generally no reversal of the burden of proof, courts can draw conclusions from the breach of the secondary burden of proof that are to the detriment of the negligent party. As a result, this can come close to a de facto reversal of the burden of proof.

Practical significance of the secondary burden of proof In court practice, the secondary burden of proof often arises in complex cases, particularly in areas such as copyright law, competition law, IT law or liability cases in which one party typically has decisive information. A prominent example is the area of copyright infringements on the internet, where the owner of the connection is regularly asked to specifically state who had access to their internet connection at the time of the offense because these facts are within their sphere of influence.

Legal basis and case law on the secondary burden of proof The secondary burden of proof is not expressly regulated by law, but has been developed by case law, in particular on the basis of Section 138 of the German Code of Civil Procedure (ZPO), which establishes an obligation to provide truthful and complete information. The supreme courts, in particular the Federal Court of Justice (BGH), have specified and further developed the principles and requirements of this legal concept in their rulings.

Conclusion on the secondary burden of presentation In summary, the secondary burden of presentation is an important procedural instrument that serves to compensate for existing information imbalances between the parties in civil proceedings. By establishing a substantiated burden of presentation on the party that has exclusive access to relevant information, it contributes to the fair distribution of procedural responsibilities and ultimately to the determination of the material truth in the legal dispute.