Aviva chair buys shares post-AIG acquisitionColefax CEO and directors sell shares in tender offerSirius Real Estate CEO sells 500,000 sharesGeorge Culmer, chairman of Aviva (AV.), bought 110,675 shares at 396p for a total value of £437,799 on 25 September.The purchase comes as the UK insurer announced it was buying AIG's UK protection business for £450 million and almost a month after Aviva...

The stock market's smallest and riskiest companies have always held fascination for private investors. On the premise that 'elephants don't gallop, but fleas leap,' to borrow Jim Slater's often quoted phrase, it's easier for a tiny company to double its size, and investor's money, than for a big one. Let's face it, a blue chip company worth £1 billion will find it much harder to double or...