Wren said enough to infer that big data deals by Interpublic Group and Publicis were a waste of money. Time will tell, but the current regulatory environment around data privacy may lend itself to a prudent approach – if regulators around the world take genuine action. 

There is risk attached to both approaches - investing big to own first party data before regulation bites, or paying incrementally for data-as-a-service to avoid stranded assets. But Omnicom appears to have the market's backing. While shares took a hit on its most recent quarterlies, it has generally been trending upwards in the year to date, whereas Interpublic Group has been more lumpy, and Publicis Groupe's trend is negative.

Wren, usually more nuanced in his choice of words than some other holding group CEOs, has form when it comes to zigging when the market is zagging.

The markets do not always call it right, but there's a whole lot of dust yet to settle.