There are discrepancies about the ideas that proviso is an agreement independent and apart from contract that bounds neither of the exchangeable items posited in the contract; not either the intention or the intended and that the contract is only a container of the conditions’ occurrence within which the proviso can be actualized or that the proviso constrains the contract. From jurisprudents’ perspective, there is no independent discussion about the contract change following the setting of a proviso rater its examples, like virtual will and transformation, have been expressed. Contract change has also not been independently discussed by the jurists rather references have been made thereto within the format of other discussions. Keeping this in mind, the issue would become what change might be brought about in the contract after a proviso was found essentially contradicting the contract? The current research paper has been conducted based on a descriptive-analytical method. It was concluded that setting expediency-contradicting proviso might cause alteration and change in the contents’ expediencies such as the elimination of the customary and canonical effects of the contract in absolute terms without bringing about a new effect and/or cause new effects based on the agreement reached within the format of proviso by omitting these effects and their instrument. It is in such a manner that the change in the expediency might sometimes cause decline therein and, put it differently, the contract expediency might be totally diminished without the possibility of imagining an expediency for a new contract and it is also sometimes the case that the change in the expediency results in the omission of the apparently inserted contract’s expediency following which a new expediency can be conjectured. Thus, in this case, proviso interprets the parties’ wills and plays the role of a constraint.
