Narrated 'Abdullah (ra) said, I heard the Messenger of Allah ﷺ say "If somebody buys date-palms after they have been pollinated, the fruits will belong to the seller unless the buyer stipulates the contrary. If somebody buys a slave having some property, the property will belong to the seller unless the buyer stipulate that it should belong to him."
سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ مَنِ ابْتَاعَ نَخْلاً بَعْدَ أَنْ تُؤَبَّرَ فَثَمَرَتُهَا لِلْبَائِعِ إِلاَّ أَنْ يَشْتَرِطَ الْمُبْتَاعُ وَمَنِ ابْتَاعَ عَبْدًا وَلَهُ مَالٌ فَمَالُهُ لِلَّذِي بَاعَهُ إِلاَّ أَنْ يَشْتَرِطَ الْمُبْتَاعُ وَعَنْ مَالِكٍ عَنْ نَافِعٍ عَنِ ابْنِ عُمَرَ عَنْ عُمَرَ فِي الْعَبْدِ