Kharijah bin Zayd (may Allah have mercy on him) narrates from his father (may Allah be pleased with him) that he was the first person to apply 'awl (proportional reduction) to the shares of inheritance, and the most he raised them by was two thirds.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الفرائض / 12454