In a surprising result, Satyapragyan succumbed to time pressure to hand full points to his Andhra Pradesh rival P Praveen Prasad in a keenly contested fourth round encounter.
Playing black side of Queen's Gambit accepted variation, Das displayed sheer skills in the Queen and Pawn ending to garner full points against his Karnataka rival Arvind Shastry in 45 moves.
IM Saptarshi Roy of Railways and G Akash of Tamilnadu joined Das at the top of the table after defeating Vignesh N R (TN) and Women Grandmaster Kiran Manisha Mohanty (Orissa) respectively.
Earlier in the third round, top seed and defending champion Vikramaditya Kulkarni drew with IM R Balasubramaniam after a marathon match that lasted 123 moves.
Second seed IM Satyapragyan settled for half point against E P Nirmal of Kerala and talented Orissa youngster Utkal Ranjan Sahoo outwitted IM C Praveen Kumar of Railways.