Some 13 electricians on a Romford rail site were set to be taken on directly by T Clarke as Socialist Worker went to press.
This followed protests by the workers about being employed through an umbrella tax scam.
The company sacked two Unite union shop stewards on Friday of last week, sparking protests at the site gates.
Unite steward Graeme Boxall told Socialist Worker, “These companies have got fat off the JIB agreement, getting contracts they couldn’t otherwise.
“They are supposed to support union recognition, but they see union membership as a declaration to come for you.”
On Monday of this week a picket closed the site down. Trucks were turned away as both directly employed and agency workers refused to work.