Alliance Boots chairman Stefano Pessina survived an investor rebellion when Walgreens' shareholders voted narrowly against a proposed bylaw that could have restricted his power at the US pharmacy chain.

Last week's vote at Walgreens' annual shareholders meeting in Chicago came after US investor CtW Investment Group expressed concerns about Mr Pessina's "undue influence" over the company following the merger between Walgreens and Alliance Boots in June 2012.

CtW, a major investor in Walgreens, said in a letter to shareholders in December that there had been a "sudden concentration of ownership in a single individual", with Mr Pessina holding an 8 per cent equity interest in the US chain, a share that could double in 2015.

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	Senior analyst Michael Pryce-Jones, speaking on behalf of CtW before the vote at the meeting on Wednesday (January 8), said that there was a "real risk" that Mr Pessina's influence "could ultimately sway the direction of this company and the composition of the board in the future".

The proposal was for a bylaw that would give Walgreens shareholders the ability to nominate directors to the company's board, and was defeated after only 43 per cent voted for the proposal. Walgreens' board of directors, of which Mr Pessina has held a position since 2012, unanimously recommended a vote against the proposal, the meeting heard.

CtW said in the December letter that the bylaw would enhance accountability at the firm and provide a "critical safety valve" against a "risky and ambitious" management strategy that had seen Mr Pessina gain power at the firm.

"This represents a sudden concentration of ownership in a single individual and marks a significant shift in Walgreens' governance structure, raising questions about whether Mr Pessina could have undue influence," the letter said. Alliance Boots said it did not want to comment on the vote.

Walgreens purchased a 45 per cent stake in Alliance Boots in June 2012 in a £4.27bn deal, with the option to buy the rest of the company in 2015.