The 6th-Case-affix is used when used in connection with words ending with affixes having the sense of the affix atasuca -- dakṣiṇottarābhyāmatasuc [[5.3.28]].,
The affix अतसुच् is ordained by 5.3.28.
Ex. ग्रामस्य दक्षिणतः उत्तरतः पुरस्तात् उपरि वा 'to the south or north, foremost, in or above the village.',