Papers lodged at the High Court in Belfast on behalf of the victims' relatives claim damages for alleged negligence in the supervision and monitoring of Arthur McElhill.
McElhill, 36, was found to have torched his two-storey terraced house in November 2007.
The inferno in Lammy Crescent claimed the lives of his partner, Lorraine McGovern, 29, and their five young children.
A coroner later ruled that McElhill burned the house because Ms McGovern threatened to leave him.
She died in the blaze along with children Caroline, 13, Sean, seven, four-year-old Bellina, one-year-old Clodagh and 10-month-old baby James.
McElhill, a heavy-drinking depressive with previous rape convictions, was also killed.
He was having sex with a 16-year-old girl in the weeks before the fire.
Proceedings have been issued against the Western Health and Social Care Trust and the Chief Constable of the PSNI.
The action, brought by Kevin McGovern, is in the early stages of going through review hearings to check progress in the case.
No-one was available for comment from the plaintiff's solicitors.
But a copy of the writ sets out details of the claim against the two defendants.
It claims damages on behalf of Ms McGovern and her children.
The papers allege that the loss sustained by the estate of each of the six deceased was due to the negligence and breach of duty of the defendants in three areas: the supervision, monitoring, care and control of McElhill; the care and supervision of the six deceased and discharge of the defendants' statutory duties and exercise of their statutory powers on or before November 13, 2007.
A Northern Ireland Courts Service spokesman confirmed that the action is ongoing.
A further review of the case has been listed for October.