Ibn 'Umar reported the Messenger of Allah ﷺ as saying:
If anyone emancipates his share in a slave, he should emancipate him completely if he has enough money to pay the full price ; but if he has none, he will be emancipated to the extent of his share.

حَدَّثَنَا إِبْرَاهِيمُ بْنُ مُوسَى الرَّازِيُّ، أَخْبَرَنَا عِيسَى بْنُ يُونُسَ، حَدَّثَنَا عُبَيْدُ اللَّهِ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، قَالَ قَالَ رَسُولُ اللَّهِ ﷺ " مَنْ أَعْتَقَ شِرْكًا مِنْ مَمْلُوكٍ لَهُ فَعَلَيْهِ عِتْقُهُ كُلُّهُ إِنْ كَانَ لَهُ مَا يَبْلُغُ ثَمَنَهُ وَإِنْ لَمْ يَكُنْ لَهُ مَالٌ عَتَقَ نَصِيبُهُ " .