"It is undoubtedly his, and it is not permissible for the giver to stipulate any conditions or exceptions." Abu Salamah said: "Because he gave it as a gift and thus, it is subject to the same ruling as the estate, and the condition (that it will revert to the giver on the death of recipient) has become invalid."
أَنَّ رَسُولَ اللَّهِ ﷺ قَضَى فِيمَنْ أُعْمِرَ عُمْرَى لَهُ وَلِعَقِبِهِ فَهِيَ لَهُ بَتْلَةٌ لاَ يَجُوزُ لِلْمُعْطِي مِنْهَا شَرْطٌ وَلاَ ثُنْيَا قَالَ أَبُو سَلَمَةَ لأَنَّهُ أَعْطَى عَطَاءً وَقَعَتْ فِيهِ الْمَوَارِيثُ فَقَطَعَتِ الْمَوَارِيثُ شَرْطَهُ