The trio overtook second-round leader Marcel Siem, who stumbled to a two-over 73 with a pair of double-bogeys on the back nine.
Rory McIlroy and Graeme Green failed to muster a charge. Both finished with 72s and were tied for 32nd place.
Howell, who was McIlroy's playing partner, could do no wrong. He hit a streak of three consecutive birdies on the back nine and added two more on 15 and 16 to take a share of the league.
"I have not been in the best of form, so I was intrigued how I was going to be playing with Rory. He's the star of world golf," said Howell. "But there were no nerves and I think I was inspired by the atmosphere."
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