Centrica chief executive Sam Laidlaw’s move to raise his stake has turned out well after shares in the utility rose as investors opted for defensive stocks as the market slumped on credit fears.

Laidlaw invested about £251,200 to buy 75,000 shares at 335p each, taking his stake to 341,000 shares.

Centrica, which under the British Gas brand is the biggest supplier of gas in the UK, reported better than expected interim results at the beginning of August. Operating profit rose from £692m to £1.25 billion in the six months to June 2007 while revenues fell from £8.73 billion to £8.59 billion.

- David Weymouth, the operations and IT director of Royal & Sun Alliance, has bought 56,000 shares in the insurer at £1.35 each. He has been on the board since the end of June and did not own any RSA shares prior to this purchase.

Directors Clare Salmon and John Maxwell also bought shares later in the week. Salmon, who joined in May, made her first acquisition after buying more than 21,000 shares at £1.38 each. Maxwell acquired nearly 36,000 shares at about the same price, raising his stake to 303,000.

RSA’s shares have been drifting downwards since the middle of May. The recent floods have proved costly, with claims totalling £120m. For the six months to June, it reported a 6% rise in net written premiums to £2.99 billion. Profit after tax was flat at £237m. Annualised expense savings of £130m have been achieved and there are plans for 700 more job losses.

Directors have in-depth knowledge of their businesses, so it can pay to track their moves. Every week Digitallook.com reveals the bosses who have bought or sold big stakes.

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