McDonald would not say how much money in damages his clients want, but he predicted it could be millions of dollars.
An attorney representing two tenants in a separate action said the lawsuits will likely be combined.
Tenants Jorge and Lucia Flores are also suing the building's owner for injuries Jorge Flores received as he attempted to flee the burning building.
From the filing:
After Plaintiff JORGE FLORES left his apartment and as he made his way down the hallway, he was hit with a blast of heat. ... [He] raised his hands to protect his face and turned away. ... As a result, Plaintiff suffered third degree burns to the back of his hands and to parts of his face, neck, ears, and/or head.
The lawsuit says Flores made his way back along the hallway in complete darkness and "noticed that sheets of skin were falling off his hands" after entering a neighbor's apartment. He then got to the fire escape and began lowering it "until it became caught on a commercial awning and would not descend to street level," according to the filing.
Firefighters eventually brought a ladder to the fire escape and helped him down. Flores was hospitalized for a month.
Attorney Gordon Kaupp, who represents Jorge and Lucia Flores, said his client was in a medically induced coma for weeks. His face and hands are likely permanently scarred, Kaupp said.
The owner, Hawk Lou, has yet to respond to questions about the legal actions against him, but in the days after the fire, he disputed allegations that the building was not up to code and expressed sorrow for the plight of his tenants.
"The fact is that I did my part to maintain the building," Lou wrote in an email to KQED. "I feel so terrible and sorry for [what] has happened to all the tenants, the injuries and death."
The fire killed one resident, Mauricio Orellana, despite firefighters' desperate attempt to rescue him.
It was among several apartment blazes that led to a push by two San Francisco supervisors for better enforcement of the city's fire code and more sprinklers in older apartment buildings like the one on 22nd Street.
The blaze also led the fire marshal at the time to acknowledge weaknesses in the fire department's recording of safety problems in the city's apartments, after it was revealed that several exits in the building were blocked.
This report was updated with a response from Gordon Kaupp.