Australia's largest privately owned construction company, Grocon, has been charged over a fatal wall collapse in Melbourne.

Bridget Jones, 18, her brother Alexander, 19, and French national Dr Marie-Faith Fiawoo were killed when a brick wall collapsed on them in high winds on Swanston Street in Melbourne's CBD in March 2013.

The wall was on a Grocon building site.

A Grocon spokesman has confirmed WorkSafe has filed criminal charges in the Melbourne Magistrates Court against the construction company and Aussie Signs, which was contracted to hang advertising on the wall.

It is believed the charges allege a sign attached to the wall was unsafe and that Grocon should have eliminated or reduced the risk in accordance with Victoria's Occupational Health and Safety Act.

Grocon chairman Daniel Grollo has issued a statement saying he cannot respond at this stage as he is yet to learn the specific details of the allegations against the company.

It is believed the company could be facing up to $9 million in fines if found guilty.

In preparations for the coronial inquest last year, the Victorian State Coroner heard that personnel associated with Grocon were refusing to give witness statements about the fatal accident.

A police investigator told the Coroners Court that Grocon had provided no witness statements to the investigation other than that of an archaeologist who had once performed a dig on the site.

Police investigators also told the court they wanted to obtain an engineering survey from Grocon, which the company said was not relevant and refused to surrender.

Victorian Coroner Judge Ian Gray said he wanted to see the survey irrespective of its perceived relevance, and said it should be made available to the inquest.

The inquest was initially scheduled for June 2014, but has since been delayed and has no fixed date scheduled.