P&G is one of the bedrock international clients for Grey, alongside Mars and GlaxoSmithKline. Of all of those, it is P&G that is the most important because it is Grey's largest client, accounting for almost 11% of Grey Worldwide's $1.3bn (拢712.2m) in revenues.
Sharing P&G is an important plus point for Publicis, although according to a report in the Wall Street Journal, P&G has recently made it clear to Publicis chairman and CEO Maurice Levy and Grey chairman Meyer that it will not consolidate its advertising with one agency group.
Others also point to the fact that Meyer and Levy can do business together. They are on good terms and are reported to have dinner together when the 77-year-old American is in Paris.
That all makes a pairing with Publicis seem to many like a more natural fit, if, as has already been done, Interpublic Group is ruled out of the running because of its balance sheet problems and Havas because of its size.
That leaves only Omnicom Group, WPP Group and Publicis Groupe. Of the three France's Publicis is seen as by far and away the best fit.
WPP is problematic. Not only has it swallowed several large acquisitions in the last few years -- from Young & Rubicam to Tempus and Cordiant -- but P&G rival Unilever is also one of its major international clients.
Despite a changing attitude to client conflict brought about by the ever increasing size of the advertising holding companies, Unilever and P&G still do not share the same agency.
A Unilever spokesman said: "In the past, we've not seen it to be such a good idea."
However, others suggest that if the clients are housed in separate agencies there is a clear way around client conflict and on this basis some would not rule out the schmoozing talents of WPP chief executive Sir Martin Sorrell to pull something out of the bag, assuaging P&G and Unilever, keeping them at arm's length in different parts of WPP.
That leaves Omnicom Group, which does not do much business with P&G and a deal with Grey could open the way for that.
However, analysts point out that mega mergers have never featured in Omnicom's history in the same way they have in that of rivals Publicis and WPP, which have made their names on the back of a number of larger deals.
However, with investment banks Goldman Sachs and JP Morgan Chase only just called in to assess the options, the battle for Grey has only just begun.
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