NEW YORK--Gary Stockman is to exit his role as global CEO of Porter Novelli, with a search currently underway to identify his replacement.

Stockman will step down from his position at the end of July, after a tumultuous four-year period heading the Omnicom Group agency. Porter Novelli has suffered some significant account losses in recent years, although it is understood that Stockman's departure is part of a planned process to reinvigorate its offering.

In recent months, the firm has won significant new global business from LG Mobile and SanDisk, while its European operation has also stabilised and grown over the past two years.

His exit follows the departure of president Julie Winskie earlier this year. 

“For more than a decade I’ve been committed to the transformation Porter Novelli leads for our clients every day," said Stockman. "After nearly five years as CEO, it’s time for a new experience.”

Stockman was an executive with the technology communications firm Copithorne and Bellows when it merged with Porter Novelli in January 2000, and he co-led the integration of the two companies. 

“Gary has played a critical role in the development of Porter Novelli’s future," said Dale A. Adams, CEO of Diversified Agency Services (DAS), the Omnicom Group division that houses its PR operations. "His commitment to the value of public relations in a modern world of communications is unparalleled. We wish him all the best.”

Significantly, given the merger speculation that has dogged Porter Novelli in recent years, Adams added that “the Porter Novelli history and its future make it a valued member of the Omnicom family and we will fully support the leadership transition and appointment of a new chief executive officer.”

Michael Ramah, global director of strategy and a 25-year Porter Novelli veteran, will work with Stockman during the transition and assume the duties of acting CEO on Stockman’s departure.

The departures of Stockman and Winskie mean that, of Porter-Novelli's global leadership triumvirate, only global president and CFO Anthony Viceroy remains at the firm.

Separately, Porter Novelli global CMO Michael Goldberg recently left the firm after less than six months to return to the advertising world.