Sir Martin Sorrell has been trying his best in recent days to make TNS shareholders increasingly uneasy about the nil premium merger with GfK. He has been talking down the merger, questioning how the pair reached merger synergies of £76 million and saying the merger makes little sense. He even went to the trouble earlier this week of making an official statement simply to say the Bavarian Ministry of Commerce and the City of Nürnberg intends to vote against the proposed merger.

The motive behind these actions is not clear. Does Sir Martin really believe the merger makes no sense? Is he concerned about increased competition with his market research business Kantar if GfK and TNS are united? Could he be trying to drive down the TNS share price? Or is he simply trying to convince the market that TNS would be much better off in the hands of WPP?

Judging from comments Sir Martin made earlier this year about wanting to grow his market research arm, TNS seemed the perfect opportunity for WPP. However, WPP’s latest offer of 260p per share is unlikely to win round shareholders, with some indicating that they want closer to 300p. Sir Martin has threatened in the past to make a hostile approach, but he will probably have to dig deeper if he is wants to get shareholders on side.

What is clear is that he has just days to make a final decision, with the Takeover Panel last night setting a ‘put up or shut up deadline’ of July 9 for WPP to make formal offer for TNS or pull out.

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