The receiver of Lane Walker Rudkin has laid a complaint with the Serious Fraud Office.
The Christchurch-based clothing manufacturer went into receivership in April, owing more than $121 million to creditors.
The receiver, BDO Spicers, will not say what concerns it has raised with the Serious Fraud Office.
The union representing the 228 workers who were made redundant from its factories in the North and South Islands says it is pleased the receiver has laid a complaint. The National Distribution Union's general secretary, Robert Reid, says the workers have told him they want a full exploration of what went wrong at the company.
Mr Reid says he expects any investigation will centre around Lane Walker's owner, Ken Anderson, who had complete control of the company.
