29 CFR § 452.116 - Determining validity of ballots.
Generally, a labor organization has a right to establish reasonable rules for determining the validity of ballots cast in an election. However, where the union has no published guides for determining the validity of a voted ballot, it must count any ballot voted in such a way as to indicate fairly the intention of the voter. An entire ballot may not be voided because of a mistake made in voting for one of the offices on the ballot.
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