Agency.com, Agency Republic, and Hyper, the digital arm of Fallon, were all involved at an earlier stage. The incumbent, Profero, which has held the business for five years, declined to repitch.
Grand Union will now take responsibility for all of Ask.com's UK digital advertising and will aim to tempt users away from Google in a bid to increase Ask.com's share of the £1.2 billion UK search sector.
The search engine kicked off the review last month after the launch of its "Information Revolution" ad campaign. The push, created by Fallon and Profero, came under criticism for driving consumers to a website organising an "information revolution", which turned out to be a branded site for Ask.com.