Disabled workers occupy Remploy HQ
The GMB union said the action at the offices of Remploy in Leicester was part of a fresh initiative to save jobs.
They left the building after five hours, saying they had been promised more information.
Unions have held a series of strikes at Remploy factories and have announced a five-day walkout at sites in Chesterfield and Springburn, Glasgow, from September 3.
GMB national officer Phil Davies said: "We are asking the public to support our members who are trying to find out who they will be working for as no information about the sale of these two factories has been given to the employees or the trade unions."
Half of Remploy's 54 factories are to close by the end of the year, 18 will close or be sold next year and the remaining nine face an uncertain future.
A number of factories closed last week under controversial Government plans to switch spending to help individual workers find jobs in mainstream sectors.