Executives close to the situation said Mr. Whitehead made an unsuccessful eleventh-hour bid to keep the business.
Seoul executives want to combine the estimated $290 million U.S. media buying for Hyundai and sibling Kia Motors America Co. The winner is also now expected to get Hyundai's $70 million local dealer group media account.
Aegis Group's Carat USA is considered the front-runner against remaining contender independent Horizon Media, both New York. Cordiant Communications Group's Bates West, Irvine, Calif., was not included in the review but was said to be trying to get into it.