Former steelworkers who lost their pensions when their employer went bust have won permission to fight the case in the European Court of Justice.
It follows legal action by unions on behalf of the former employees of Allied Steel and Wire (ASW) in Sheerness in Kent, and Cardiff.
The unions Community and Amicus have been fighting for pensions since ASW went bankrupt in 2002, affecting about 1,000 workers.
The case is expected to be heard in the European Court of Justice next year.
Legal action was launched over what the unions claimed was the failure of successive governments to implement European law to protect workers’ pensions when their employers were declared insolvent.