Companies buy back stock to boost faltering Nasdaq...A number of US companies are planning to buy back their own shares to help boost the re-opening of the New York Stock Exchange and the Nasdaq. 3Com and Cisco have already pledged to buy back their own stock. Networking giant Cisco is expected to buy back around $3bn of its own shares through a buyback programme to be detailed in October. Meanwhile, 3Com is planning to buy back options worth around $1bn through a programme it began in 2000. For the most part, the decision to repurchase shares came this weekend, as executives announced they felt confident not only about their businesses but also in the financial markets as a whole. Other companies announcing plans to buy back their shares today include American International Group, Coca-Cola, FleetBoston Financial and Pfizer.