The agency can sue companies if they miss more than $1 million in payments to their defined-benefit plans.
The agencies have repeatedly sued to claim that some or all of the money was theirs, to use as they saw fit.
Should the federal agency not sue Allstate, the agents would then be free to file their own suit.
The agency is suing to shut down the drug maker.
A big computer marketer and its former agency are suing each other.
The agency countersued, and also sued the town of Tiburon.
In 1997, the agency, later joined by the state, sued to force the city to adhere to a timetable for building a treatment plant.
In response, Johnny's agency sued the magazine's publisher, Bungeishunjū.
Mr. Walker said the agency had sued 15 manufacturers.
The agency is suing the directors for $17.2 million.