The petition was filed on behalf of Yannick Gagne, owner of the Musi-Café, which was destroyed by the blast, and Guy Ouellet, whose wife died in the disaster.
The applicants are claiming compensation for material losses and moral damage suffered by the community.
Emergency workers have recovered 35 bodies from the area around where a portion of the train carrying crude oil derailed and exploded on July 6. Another 15 people remain unaccounted for but are presumed dead.
Lac-Megantic lawyer Daniel Larochelle, whose office was destroyed in the explosion, filed the preparatory motion to file a class-action lawsuit Monday morning.
Larochelle says he has been approached by several other residents to join the lawsuit.
The motion was filed in Sherbrooke, Que., because the courthouse in Lac-Mégantic remains in the town's closed-off red zone.
The structure was spared by the fire, although it has yet to reopen to the public.
The lawsuit targets 16 defendants, including the MMA's chairman and the conductor of the train the derailed train.
Also cited as a defendant is train operator Tom Harding.
Harding's role is a central question in investigations into the tragedy. His own employer called him a hero one day, then announced the next he had been suspended amid concerns about his role in the disaster.
Yves Bourdon, a member of MMA's board of directors, said Monday he was not in a position to comment.
"No one has been authorized to make any comments at this stage," he said, adding he had not seen the lawsuit.
Bourdon said the whole team, including chairman Edward Burkhardt, were told not to make any comments.
"Mr. Burkhardt can do what he wants, but we are all under the same orders," he said.
The amount of compensation sought is not yet known.
The action seeks recovery for damages suffered by people who lost loved ones in the explosion and on behalf of people who were injured. Claims are also being sought for property and business losses.
Emergency cheques cut by province
Immediate compensation started to trickle into Lac-Mégantic in the form of emergency cheques issued by the provincial government to residents devastated by the train derailment and explosion.
An estimated 1,500 cheques for emergency assistance are expected to be issued to families who were evacuated from the centre of town in the wake of the disaster.
About 70 cheques for $1,000 — intended to offset immediate needs like shelter and food — were issued this morning at the temporary provincial office set up in town.
The Quebec government has promised a three-tiered, $60-million plan to help the residents of Lac-Mégantic manage in the wake of the emergency and to rebuild the town.
It includes $25 million for urgent relief, $25 million for rebuilding the devastated downtown core, and $10 million for longer-term economic aid.
Some of the payments were available to residents today, but there were some glitches.
CBC's Peter Tardif said he spoke with one resident who lives in the designated area but wasn't on the list of approved recipients.
Quebec's Public Security Minister Stéphane Bergeron, on site in Lac-Mégantic Monday morning, said that problem has since been resolved.
Bergeron said he met with people waiting in line to receive the cheques this morning, and they seemed appreciative.
"Everyone is being very patient," he said. "We're certainly trying to give them all the support possible in these circumstances. You have to understand that many people are living through an absolutely horrible tragedy."
Heat plagues emergency workers
Bergeron said the intense heat rolling through southern Quebec has proved difficult for the emergency workers still trying to recover remains inside the red zone at the centre of town.
Officials said yesterday crews must be replaced every 20 minutes because they have to wear heavy equipment and masks in temperatures higher than 30 C.
The incredible amount of destruction at the scene has also made the recovery process has been slow, with the official death toll rising by a few every day.
Two more bodies were pulled from the rubble on Sunday, bringing the official number of those recovered to 35.
Authorities demolished two buildings Sunday because they were said to be unstable and posed a threat to crews working there.