Is filing additional documents permitted during appeal?

Yes. In that case that would examine whether these documents could be obtained and produced earlier with due diligence if yes then it normally is not allowed. Or.41 R 27 is the relevant provision :-

27. Production of additional evidence in Appellate Court.- (1) The parties to an appeal shall not be entitled to produce additional evidence, whether oral or documentary, in the Appellate Court. But if—

(a) the court from whose decree the appeal is preferred has refused to admit evidence which ought to have been admitted, or

(aa) the party seeking to produce additional evidence, establishes that notwithstanding the exercise of due diligence, such evidence was not within his knowledge or could not, after the exercise of due diligence, be produced by him at the time when the decree appealed against was passed, or

(b) the Appellate Court requires any document to be produced or any witness to be examined to enable it to pronounce judgment, or for any other substantial cause, the Appellate Court may allow such evidence or document to be produced, or witness to be exam med.

(2) Whenever additional evidence is allowed to the produced, by an Appellate Court, the court shall record the reason for its admission.

The Court has wide powers under order 41 Rule 23A to order a re-trial 

Good Luck !

Bharat Chugh - Advocate Supreme Court of India

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