Saatchi & Saatchi is suggesting that it will remain independent as industry speculation about a possible takeover of the British media and advertising company continues. Saatchi & Saatchi shares surged 10% last week on rumors of a takeover by France's Havas Advertising. "Independence suits us," Saatchi & Saatchi Chief Executive Bob Seelert said. "We're highly charged. New business, margins and profits are all up, and the network has a fresh vibrancy about it." Seelert said the group's earnings rose 61% in 1997, because of cost-cutting and the addition of new accounts such as Delta Air Lines Inc. and France Telecom. Havas is rumored to be interested in Saatchi because it has a strong presence in the U.S., where the French company has relatively little business.