This hadith has been narrated on the authority of Shu'ba with the same chain of transmitters (and the words are):

" He who emancipates a portion in a slave, he should (secure full) freedom for him from his property."

وَحَدَّثَنَا عُبَيْدُ اللَّهِ بْنُ مُعَاذٍ، حَدَّثَنَا أَبِي، حَدَّثَنَا شُعْبَةُ، بِهَذَا الإِسْنَادِ قَالَ ‏

‏ مَنْ أَعْتَقَ شَقِيصًا مِنْ مَمْلُوكٍ فَهُوَ حُرٌّ مِنْ مَالِهِ ‏

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