Kumar contended Yeddyurappa had violated election rules while declaring himself as the President of Karnataka Janatha Party.
Prasanna Kumar formally handed over the reigns of the party to Yeddyurappa at a rally in Haveri on December 9 last year.
Yeddyurappa took over the party after quitting ruling BJP, upset over his "neglect" by party central leadership.
The Election Commission subsequently recognised Yeddyurappa as the President of KJP and rejected Prasanna Kumar's claim as the founder President.