Mahabharata 13.47.54

वैश्यापुत्रेण हर्तव्याश्चत्वारोंऽशाः पितुर्धनात्पञ्चमस्तु भवेद्भागः शूद्रापुत्राय भारत

vaiśyāputreṇa hartavyāścatvāroṃ'śāḥ piturdhanātpañcamastu bhavedbhāgaḥ śūdrāputrāya bhārata

Our plain-language meaning of this verse is waiting for scholar review.