Case: A woman (=pl) who is in the process of divorce wants to collect her ketuba, which has a very high shekel sum in it. The husband (=def) claims that he wrote such a large sum in exchange for his receiving half of the apartment she owned. He says that when he later decided to give her back full ownership of the apartment, she relinquished her rights to the special ketuba. She denies this claim. There are two noteworthy elements to the ketuba: the large element of the ketuba is written in the section that deals with property she brought into the marriage for him to keep (nichsei tzon barzel); there are two blank lines between the end of the body and the signatures.

Ruling: It is possible to read the ketuba in a manner that there is a linkage between his receiving part of the apartment and his obligation for the large ketuba, but that is not clear. Normally we say that he who needs the document to obtain money has to prove that the language is to be read as proves his case. However, here it is different because def’s obligation to her definitely took effect, and the question is only whether he paid it off, which he needs to prove. Even when one who owes money has witnesses that he gave money to the creditor but did not know in what context, he can claim that it was for another debt upon which there is no contract (Choshen Mishpat 58). Therefore, we accept pl’s claim that the full obligation in the ketuba is unconditional, and def needs to bring proof that he gave her something as payment.
In general, a document that has more than one blank line before the signatures is an invalid document because its holder can add a line with whatever he wants (Shulchan Aruch, CM 45:6). However, the situation is different when the couple leaves a copy of the ketuba at the Rabbanut offices. Although we are of the opinion that one cannot use that ketuba to extract payment, that is because the wife may have already received payment with the main ketuba. However, it can be used to prove that the content of the main ketuba is not a forgery since no one has access to the Rabbanut ketuba. Additionally, that which one cannot use a document which leaves room for forging is to extract money from those who bought property from the debtor. However, one can extract payment from the debtor (ibid. 7). While the debtor can claim in such a case that he already paid (ibid.) that is only if there is question whether there was an act of payment. However, over here, when everyone agrees about the obligation and there is only a question whether to consider the return of ownership to pl as payment of the ketuba, the problem with the ketuba is not important. It is also difficult to claim that a ketuba was already paid because a ketuba is meant to be paid only after the marriage is dissolved (by divorce or the husband’s death), and one needs proof that he paid a debt early (Bava Batra 5a).