The protest petition was filed by Zakia Jafri, whose husband Ehsan Jafri, a former Congress MP, was killed in the Gulbarg Housing Society massacre along with 67 others.
"Satyamev Jayete! Truth alone triumphs," Modi tweeted on micro-blogging site Twitter.
The verdict by Metropolitan Magistrate B J Ganatra came as a huge relief to the BJP's prime ministerial candidate in the run up to the 2014 general elections.
Image: A supporter of Narendra Modi shows the victory sign
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