An unregistered marriage is legal if there is offer and acceptance along with consideration in the contract of marriage. Non Registration of marriage is an offense but that cannot nullify the contract of marriage even if it is verbal.
This principle is laid down in number of judgments of the superior courts of Pakistan. In many parts of Pakistan it is still the practice that spouses get married and they live together even without registration of marriage.
Registration of marriage is a mandatory requirement of law. It is documentation of contract of marriage but in the absence of such documentation we cannot declare any marriage to be illegal or void.
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