Whose wealth is used to pay the Zakat al-Fitr for slaves held in a Mudarabah (profit-sharing) arrangement?

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If slaves intended for trade are in the possession of the working partner (Mudarib), their Zakat al-Fitr must be paid from the Mudarabah capital because their sustenance is drawn from that capital. This is based on the principle that Zakat al-Fitr follows sustenance (nafaqah), which originates from the Mudarabah capital. Zakat al-Fitr is due upon the person (the body) and is obligatory upon free individuals, whereas Zakat al-Tijara is due on the value (the asset itself).