The legal document discusses the admissibility of unregistered and unstamped sale deeds in evidence within a civil suit for declaration and injunction. It emphasizes that such documents, if not registered and stamped, are generally inadmissible as evidence of the transaction itself. However, they may be used for collateral purposes if they are independent of or divisible from the transaction that law requires to be registered. The key legal principles highlight that the question of whether a document is properly stamped and registered must be decided before proceeding further in the case, not deferred until the final hearing. Additionally, the document's purpose for being introduced in evidence—whether as part of the main transaction or for collateral reasons—determines its admissibility. In this context, if the document is directly related to the main transaction, such as a sale deed creating rights or interests in immovable property, it cannot be admitted unless properly registered and stamped. Conversely, if it is for collateral purposes and independent of the primary transaction, it may be admissible even if unregistered or unstamped. The court also clarified that mere production or marking of a document as an exhibit does not amount to proof, and the issue of stamp duty deficiency must be resolved at an appropriate stage of the proceedings.