Stocks to watch on the Australian stock exchange at noon on Tuesday:

MAH - MACMAHON HOLDINGS LTD - down 0.25 cents to 29.25 cents

MacMahon Holdings denies it received an offer from an Indian-based firm to buy its construction business before entering into a sale agreement with its major shareholder Leighton Holdings.

WHC - WHITEHAVEN COAL LTD - down 0.5 cents at $3.495

The corporate watchdog will investigate if any laws were broken when Whitehaven Coal lost more than $276 million in market value after falling victim to a hoax media release.

YAL - YANCOAL AUSTRALIA LTD - steady at $1.00

Chinese-owned Yancoal Australia has secured $US596 million ($A570.31 million) in funds from its parent company.