Shares in Post Holdings dropped after it agreed to buy Weetabix from China's Bright Food Group.
US stocks, the dollar and government-bond yields pulled back as major indexes notched their steepest declines of the year.
If other traders thought Mark Warminger wrong in buying shares others wanted to buy, they could readily choose not to deal with him.
But private equity owners may have to accept a lower price than previously sought.
IPO prospectus expected November 16
Fund manager describes irritation with market behaviour in A2 share trading.
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