The five-way tie for the 54-hole lead matched the PGA Tour record since 1970.
Singh led Woods by seven shots and O'Hair by 10 at the start of Saturday's play.
"It's nice to have to go out there and play a good round of golf and win the tournament instead of having to play a great round of golf to hopefully get myself back in the mix," said Woods, who will be after his fifth straight PGA Tour title on Sunday. "I did the work today to get myself back in the tournament."
Woods is 43-3 on the PGA Tour with at least a piece of the third-round lead.