Musannaf Ibn Abi Shaybah

Hazrat Ibn Umar (may Allah be pleased with them) narrates that Hazrat Aisha (may Allah be pleased with her) intended to purchase Barirah, so the owners said: "Will you buy her on the condition that her wala' (right of inheritance/loyalty) will be for us?" Hazrat Aisha (may Allah be pleased with her) mentioned this to the Noble Prophet (peace and blessings be upon him). The Noble Prophet (peace and blessings be upon him) said: "This condition should not prevent you from purchasing Barirah, because wala' belongs only to the one who sets free." And (Imam) Abu Hanifa's opinion has been mentioned that: this condition is invalid and not permissible.