With a trial date set for January 29, 2013, 1379 Black Saturday survivors and their families have signed up for the class action.

Plaintiff law firm Maurice Blackburn has brought the class action on behalf of Black Saturday survivors and their families, to seek personal injury claims against power distributor SPI.

The claimants allege SPI was negligent when a 43-year-old powerline owned by the power company fell and sparked the Kilmore bushfire.

The Kilmore bushfire killed 119 people throughout St Andrews, Strathewen, Kinglake, Kinglake West and their surrounds and destroyed 1242 homes.

SPI has denied any liability, and sued Victoria Police, the Department of Sustainability and Environment and the Country Fire Authority over their role in Black Saturday.

Maurice Blackburn lawyer Rory Walsh said all the parties involved were still assessing the cost of the class action, which could run into the hundreds of millions.

"The total losses suffered by individual group members in a catastrophe of this magnitude is extremely complex, however this is an issue of significant importance and one that is the focus of considerable effort and discussion amongst the parties," he said.

The next pre-trial hearing is scheduled for February 10.

Parties are due to hand over all discovery documents in March before court-ordered mediation is slated for November this year.