Havas Chief Cries Uncle

Updated from 4:27 p.m.

Embattled Havas (HAVS Quote) chief executive Alain de Pouzilhac is stepping down as the head of the French ad holding company.

The move comes just two weeks after Havas shareholders embraced dissident shareholder Vincent Bollore in a June 9 vote, giving him four seats on the ad firm's board. Since then, the rebel shareholder has upped his stake in the company to 24%.

While de Pouzilhac vowed last week in a memo to employees that he would continue on in his role, it became clear that his leadership was untenable.

In a postclose statement, Havas said Richard Colker would serve as interim CEO, while directors Ed Eskandarian, Fernando Rodes and Jacques Seguela will "take responsibility for the Group's executive functions."

Speculation continues to swirl around Jean Marie Dru, CEO of Omnicom's (OMC Quote) TBWA\Chiat\Day Worldwide, as a potential permanent replacement for Pouzilac.

Bollore Medias Investissements took a big stake in Havas last year. Bollore's nomination of four directors was loudly opposed by de Pouzilhac and the rest of the Havas board, at the time. Bollore has said he has no plans to dismantle the company, but he pointedly said he wouldn't oppose management change. "I'm no Darth Vader," the corporate raider said at a meeting earlier this month.

Bollore and de Pouzilhac engaged in a bitter dispute over the company's fate. De Pouzilhac earlier referred to Bollore's actions as a "creeping takeover" that is hurting it competitively.

The fifth-largest advertising network in the world, Havas owns Euro RSCG Worldwide, Media Planning Group and Arnold Advertising and boasts clients including Charles Schwab (SCH Quote) and Ford's (F Quote) Jaguar.

On Tuesday, shares in Havas were down 6 cents to $5.78.