The legal translator of private documents is interested in the documentary context of the ST and, more specifically, in the tacit or express remission to other documents, creating therefore, a chain of documents, where one of them is central and basic as opposed to the others, the subordinate ones. This paper particularly deals with the group or chain of documents, related because they belong to the same circumstance of issue as regulated by the legal systems, which set out the documentary requirements necessary for the existence of the basic document. The article puts forward an exercise for the translator: he is to recognise the requirements for the existence of the negotium within the basic document since they are associated with subordinate documents as a guide for him while reading in order that he gradually finds out about the explicit or implicit elements of the negotium. [Based on abstract in journal]