Playing to his strength, Chakkravarthy scored his fourth straight victory to nudge ahead of nearest rivals, displaying excellent calculation and judgement in a complicated position.
It was a Sicilian defense by David who played black and the Fianchetto variation by the Indian led to wild complexities after a central thrust.
Chakkravarthy however stayed calm despite having just five minutes in a heated middle game and the Italian erred by sacrificing a rook for Bishop.
With six rounds still to come, Chakkravarthy is now followed by as many as 12 players a half point behind. Leading this pack is defending champion and top seeded Grandmaster Abhijeet Gupta who decided to play a safe game and took a draw with fellow Indian Grandmaster Sahaj Grover.
Russian Grandmasters Anton Demchenko and Mikhail Mozharov, Peruvian Christhian Cruz, Andrey Baryshpolets of Ukraine are the other Grandmasters besides Gupta and Grover in the 12-players pack.
S Nitin scored the upset of the day upstaging Grandmaster Valeriy Neverov of Ukraine while Himanshu Sharma got the better of Italian GM Axel Rombaldoni to improve his tournament standing.
A little lower, Aniruddha Deshpande continued with his dream run in the tournament and held GM Sabino Brunello of Italy to a creditable draw.
Deshpande took his tally to three points out of a possible four and this includes an opening round victory against second seed Ivan Popov of Russia.