Extra allocation of shares made to meet overwhelming demand Perhaps predictably Betfair's London IPO this month has turned out to be a runaway success.

With prelisting orders passing expectations and the share price soaring this week on the first day of trading to reach a peak of over GBP15. So successful has the listing proved that an extra allocation of shares worth GBP 22.8 million was put on the market this week, further enriching founders Andrew Black and Ed Wray.

City AM reported as the week ended that Morgan Stanley, acting as stabilising manager, triggered an over-allocation clause after shares in the betting exchange jumped from the float price of GBP13 to over GBP15.

The mechanism obliged Black, a former professional gambler, and Wray, an ex-City trader, to sell a further 10 percent of their holding in the firm, earning them GBP1.9 million and GBP1.7 million respectively.

This was in addition to the GBP 14 million and GBP 17 million already cashed in by the pair, who founded the firm 10 years ago. Other stakeholders, including Charlton Acquisition and Balderton Capital also sold more shares, increasing the percentage of the firm available on the market to 46 percent.

This is comprised of the 15.2 percent already floated last week, an extra 1.6 percent floated through the over-allocation mechanism and approximately 30 percent already owned by staff and small shareholders. The total over-allocation sum is worth GBP 22.8 million before the deduction of underwriting commissions and expenses. The shares floated last week were worth £233.7m.