Cardno shares are soaring after an unknown buyer picked up almost 10% of the infrastructure and environmental services company for $41.6 million.
The buyer is believed to be a private equity company.
About 16 million shares, or about 9.65%, of the company traded this morning in a pre-market transaction at $2.60.
Cardno says it has not had any communication with the buyer.
Earlier in the week Cardno shares fell heavily after announcing a $200 million write down on its US and Ecuadorian businesses.
Cradno, originally an engineering practice started in Brisbane, has been hit by the downturn in resources project investment.
Its shares are now up more than 17% to $2.77.