The group had a net new business balance of $2.34 billion, well ahead of second-place finisher Publicis Media's $376 million.
Big groups such as Dentsu and WPP bought fewer agencies in 2017, while consulting giant Accenture led the way as a new entrant.
TOP OF THE CHARTS: 'Increasingly piecemeal' assignments sent creative revenue plunging by nearly 17%, but media firms saw a 5.4% revenue increase.
Even though it slashed its agency roster and reduced ad production, the FMCG giant increased its overall brand and marketing investment in 2017, especially in digital.
CAMPAIGN360 PREVIEW: The pace of change in media is so fast that by the time we’ve worked on one solution, we’re already standing at the next fork in the road. With complex forces impacting business models, the next 12 months are crucial.
Shell, which has reportedly appointed R3 to handle the process, spends an estimated $200 million on marketing annually.
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