It has been reported that a growing number of institutional WPP shareholders will refuse to back the deal. However, it is expected that despite abstentions and votes against the deal, it will be passed.
WPP has defended the 拢3m pay-off under his three-year renewable contract because of Sir Martin's personal investment in WPP.
Earlier this month, the Association of British Insurers said it had "very serious concerns about Mr Sorrell's contract". His official salary, before bonuses, is 拢839,000, down by 拢10,000 on last year. The company contributed 拢336,000 in pension payments for him, down by 拢3,000 in 2001.
Sir Martin's salary soared 80% to 拢1.6m last year, after he took a bonus of 拢731,000 in the year that the company's pre-tax profits fell 50% to 拢205.5m.
It comes amid growing shareholder concern about the deals awarded to the executives of public companies.
The vote at the AGM comes ahead of a review of Sir Martin's contract by WPP's compensation committee in August.
The review will seek to replace the current controversial incentive plan, which is known as the "leadership equity acquisition plan". Under the term of the plan, Sir Martin and a handful of other WPP executives will pocket around 拢30m.
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