Presumption of document authenticity: produced, seized, or received documents are presumed genuine unless effectively rebutted. Where a document is produced under the Act, seized from a person, or received from outside India and tendered by the prosecution against that person or a co-accused, the court shall, unless contrary proof is offered, presume the truth of the document's contents and the authenticity of signatures or handwriting, including execution or attestation; and shall admit the document in evidence even if it is not duly stamped, provided it is otherwise admissible.