The Law Code of Yājñavalkya 1.3.25

1.3.25

ekasmād brāhmaṇāder jātāḥ ekajātāḥ | pṛthakkṣetrāḥ bhinnajātīyāsu bhinnāsu strīṣu jātāḥ | pṛthagjanāḥ samānajātīyāsu bhinnāsu strīṣu jātās te ekapiṇḍāḥ kiṃ tu pṛthakśaucāḥ | pṛthakśaucam āśaucaprakaraṇe vakṣyāmaḥ | piṇḍas tv āvartate triṣu tripuruṣam eva sāpiṇḍyam iti || 1.53 ||

"Born of one man" means born from a single Brahmin or the like. "In different wombs" means born of different women of different classes. "Born of different women" means born of different women belonging to the same class; they are "of the same piṇḍa," but have "different purifications." We will explain "different purifications" in the section on ritual impurity. "The piṇḍa reverts at the third" means that the sapinda relationship extends to three generations only. || 1.53