The argument is obviously not valid if the transaction is one which is required by law to be in writing such as a transfer of land.This is not an agreement that could have been made orally.However, the actual date of signature should nevertheless be set out in the attestation clause at the end to avoid any claims that the document was intentionally misleading.Needless to say, even these methods of “backdating” a document should not be used when there was no earlier agreement and the document is just an attempt to give a false impression that something occurred on an earlier date than it did.
So as can be seen, the issue of backdating can be a contentious one.
However, he only realizes this in January and so wishes to backdate the document to December.
The event did not happen during the time period required for the benefit so an attempt is being made to pretend that it did.
However, an explanation often given by the person wanting to backdate the document is that the document is merely meant to reflect an oral agreement that has already been made and that this is just a way of documenting it.
In theory, this would appear on the face of it to be a reasonable request, as it is just a private arrangement between two parties.