Stocks to watch at noon on Friday STOCKS to watch on the Australian stock exchange at noon on Friday: AIO - ASCIANO - down 22.5 cents, or 3.62 per cent, at $5.985 Asciano shares are down after the rail and stevedore operator warned of slower growth this year and said its rail network had been damaged by the ongoing bushfires. LEI - LEIGHTON HOLDINGS - down 21 cents, or 1.16 per cent, at $17.88 Infratil plans to put aside $A100 million to invest in Australian public-private partnerships over the next few years. PPX - PAPERLINX - up 0.1 cents, or 1.82 per cent, at 5.6 cents Paper merchant PaperlinX says it isn't the company it was 12 months ago, but it still has much to do to improve its performance. Construction and maintenance group Transfield Services says it remains on track to meet its full year earnings guidance. BGA - BEGA CHEESE - up 5.00 cents, or 1.27 per cent, at $4.00 Canadian diary giant Saputo has increased its offer for Warrnambool Cheese and Butter (WCB) to $449 million, insisting its takeover of the local company would not reduce competition. WHC - WHITEHAVEN COAL - up 7.5 cents, or 4.32 per cent, at $1.81 Whitehaven Coal has lifted coal sales by 26 per cent but faces continuing weak prices.