They analyzed each closing stock price before and after the date of a public announcement and found that the average stock price 120 days before a phase III clinical trial announcement showed an increase of 13.7 percent for companies that reported positive trials and a 0.7 percent drop for those reporting negative trial results ( here is the abstract).

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The offer represents a 15.4% premium over Siam Makro's last closing price on Friday, before its shares were suspended from trade.

WSJ: Thai Tycoon Offers $6.6 Billion for Siam Makro

That is a 25.6% to its closing price Friday, the last session before word of the impending dela broke.

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This latest offer represents a premium of just 6% to the firm's closing share price on 1 August, before BMI British Midland's "surprising" decision to withdraw Heathrow and East Midlands services from Belfast International, part of the TBI portfolio.

BBC: French firm launches airports bid

The bid price is 6.6% higher than the closing price on 30 December, the last business day before the two companies confiirmed they were in talks.

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