Rule 49-O was a rule in The Conduct of Elections Rules, 1961 of India, which governs elections in the country. It described the procedure to be followed when a valid voter decides not to cast his vote, and decides to record this fact. The rule was declared by the Supreme Court in September 2013 to be incompatible with the constitution and the Election Commission of India announced that the option under this rule would not be available any more. The apparent purpose of this section was to maintain a proper record in order to prevent the election fraud or the misuse of votes.
49-O. Elector deciding not to vote.—If an elector, after his electoral roll number has been duly entered in the register of voters in Form 17A and has put his signature or thumb impression thereon as required under sub-rule (1) of rule 49L, decided not to record his vote, a remark to this effect shall be made against the said entry in Form 17A by the presiding officer and the signature or thumb impression of the elector shall be obtained against such remark.
Implications of Rule 49-O
Since the ballot paper or electronic voting machine (EVM) showed only the list of candidates, a voter could not record his vote under Section 49-O directly, but had to inform the presiding officer at the election booth. This violated the secrecy of the ballot. However, with paper ballot one could "waste" one's vote by stamping on multiple candidates; this was the standard method of giving null votes without violating secrecy before the advent of the EVM.
A hoax has been circulating which claims that if the '49-O' votes more than those of the winning candidate, then that poll will be canceled and will have to be re-polled. Furthermore, it claims that the contestants will be banned and they cannot contest the re-polling for their lifetime. This is an incorrect interpretation and was clarified by the Election Commission.
Now all the Electronic Voting Machines will have the last button as NOTA (None of the above) which means, the vote has been casted, but it is not awarded to any of the candidates.