The chief executive of WPP, the world's largest advertising group by revenue, said most of his firm's new business in the third quarter was from clients that had left rival groups Publicis and Omnicom.
WPP, which has market capitalization of £16.4 billion ($26.2 billion), posted sales that outstripped competitors in the third quarter. Its like-for-like revenues were up 7.6 percent in the three months to the end of September.
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In comparison, the U.S.'s Omnicom posted 6.5 percent growth in the quarter and France's Publicis reported growth of only 1 percent.
"Most of our new business wins have come from both Publicis and Omnicom in terms of talent – the rate of inflow into us is still running at 4-to-1. So there has been a bit of a talent outflow and a bit of a business outflow (from Omnicom and Publicis)," WPP CEO Martin Sorrell told CNBC on Friday.
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Sorrell described Publicis's third-quarter performance and fourth quarter forecast as "lacking in vigor".
"If I look at the last 8 quarters we have outperformed Publicis 7 to 1, with only one quarter where their organic growth performance at the revenue level was greater," he said
WPP did post a lower-than-expected 3 percent rise in third quarter like-for-like net sales, missing consenus of 3.3 percent growth as a result of mounting geopolitical concerns. The group also said it expected to see a slowdown in the fourth quarter.
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Sorrell said geopolitical risks had impacted corporate decision-making in the third quarter and has made clients more cautious about the future.
"The forecast for worldwide GDP growth this year has softened, as we have gone through the year. But our business as a whole at the top line in terms of business and revenue growth has been very strong," he told CNBC.
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