It stipulates the husband must not forbid her from undertaking such a mission, and is signed by both parties.
The document was first shared by Elijah Magnier, the chief international correspondent for Al-Rai Media, who stressed that the certificate was not the group officially allowing 'jihadi brides' to commit suicide missions.
Essentially, he said the woman wanted to be a suicide bomber and therefore included this as her condition in the contract.
“A woman [living under Isis] has the right to put conditions to accept the marriage,” he explained. “This woman's condition was that her husband won't deny her wish to carry a suicide attack, if Amir al Mo'mineen (Baghdadi) accepts her (previous) demand.
“She is probably very young and enthusiastic,” he added. “Her demand to be a ‘martyr’ may have been formulated in an earlier one before her acceptance of a marriage offer. So she kept her "desire to be a martyr" standing and wanted to see it registered.
“Now, she may change her mind if she becomes pregnant or has children, or she may keep her same level of enthusiasm.
“But, among her girlfriends, she can show off and say: 'I am still a martyr candidate'."
Mr Winter told The Independent: “The certificate does say that the wife’s terms are that of if the caliph consents then she is allowed to go on a martyrdom operation and her husband can’t forbid her from doing so.
“Nowhere does it refer to 'orders', nowhere does it suggest this is actually happening and nowhere does it suggest that this is a regular marriage contract. It was even being circulated among Isis as a curiosity, as something funny.”
Mr Winter said the document was tweeted by a female Isis member with the tag line “only in the caliphate” as a way of highlighting how unusual such a condition is.
“It’s an obscure expression of feminist jihadism in some sense but what it isn’t is evidence that Isis is ordering brigades of women to carry out bomb attacks,” he added.
“It is not remotely indicative of any orders from among high - that is a complete misreading of it.”