What is the ruling when two individuals deny an obligation of pledging their slave as collateral for a debt?

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When two men deny the claim that they pledged their slave as collateral for a debt owed to the claimant, the ruling is upheld by their denial. If each defendant testifies against the other, their testimony is accepted provided they are upright (adil). The pledgee (al-murthahin) has the option to swear an oath alongside each defendant to make the entirety of the slave collateral, or swear an oath alongside only one of them, making only that defendant's share collateral. If one of the defendants admits the claim, the pledge is established against him alone.