Al-Kāfi

Hadith 2031
zakatslavery-captives
3ـ مُحَمَّدُ بْنُ يَحْيَى عَنْ أَحْمَدَ بْنِ مُحَمَّدٍ عَنْ عُثْمَانَ بْنِ عِيسَى عَنْ سَمَاعَةَ عَنْ أَبِي عَبْدِ الله (عَلَيْهِ الْسَّلام) قَالَ لَيْسَ عَلَى الرَّقِيقِ زَكَاةٌ إِلاَّ رَقِيقٌ يُبْتَغَى بِهِ التِّجَارَةَ فَإِنَّهُ مِنَ الْمَالِ الَّذِي يُزَكَّى.
3. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad from ‘Uthman ibn ‘Isa from Sama‘ah who has said the following: “Abu ‘Abd Allah (a.s.), has said, ‘Slaves are not subject to Zakat unless they are for business purposes, because they are from assets that are subject to Zakat.”
Source: Shaykh Muḥammad b. Yaʿqūb al-Kulaynī