"The Messenger of Allah said: 'Ruqba is not permissible. Whoever is given something on the basis of Ruqba, it is part of his estate.'" (Using translation from Nasāʾī 3714)

قَالَ رَسُولُ اللهِ ﷺ «لَا تَحِلُّ الرُّقْبَى فَمَنْ أَرْقَبَ رُقْبَى فَهُوَ بِسَبِيلِ مِيرَاثٍ»