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Workers who say they were blacklisted by construction companies have won millions in compensation after a long-running legal battle finally ended.

The union Unite has reached a settlement with construction firms that will mean 256 workers share more than £10m in compensation.

The amount will depend on factors such as loss of income.

In some cases, the blacklist included details of worker's political views, competence, and trade union activities.

The list had been used by dozens of construction firms to vet those applying for work on building sites.

Last month, the GMB and Ucatt unions and a law firm reached a separate settlement with construction companies in the blacklisting scandal.

That claim was settled for a total of £5.4m plus millions in legal costs, with some members due to receive between £25,000 and £200,000, the union said.

The settlement with the GMB, Ucatt and law firm CGR was reached on 29 April but could not be announced until the Unite case was settled.

Analysis by BBC Industry & Employment correspondent John Moylan:

The construction industry has always denied the "blacklisting" charge. It claims blacklisting involves automatic discrimination and that this did not always happen.

But it accepts that for decades firms were involved in a secret vetting system which infringed workers' rights to confidentiality, privacy, reputation and data protection.

Campaigners say there's little difference between the two. They say the firms' denial of blacklisting is commercial - it could prevent them bidding on lucrative public procurement contracts in the future.

But key individuals who were involved in the illegal vetting system are still in senior positions within the firms. That's led unions to call for a public inquiry into what they regard as one of the most shameful episodes in British industrial history.

The GMB said it understood the total compensation for blacklisting was about £75m for 771 claimants, with legal costs on both sides estimated at £25m.

An unknown number of workers had chosen to take much lower sums offered by some of the companies involved, the GMB said.

The claims were brought against the companies Carillion, Balfour Beatty, Costain, Kier, Laing O'Rourke, Sir Robert McAlpine, Skanska UK and Vinci.

The firms said the settlement with Unite brought to a close all the claims in the litigation.

"These construction companies wish to draw a line under this matter and continue to work together with the trade unions at national, regional and site level to ensure that the modern UK construction industry provides the highest standards of employment and HR practice for its workforce," they said in a joint statement.

'Historic victory'

Dave Smith, secretary of the Blacklist Support Group, said: "Despite all of the denials and attempts to cover up their secret conspiracy, the largest multinationals in the construction sector have been forced to pay out millions in compensation.

"Make no mistake, the High Court action is a historic victory for the trade union movement against the vicious face of free market capitalism."

The blacklisting scandal came to light in 2009 following a raid by the information commissioner's office on an organisation called The Consulting Association which was based in Worcestershire.

It uncovered a list of more than 3,000 workers - which in some instances also included details of personal relationships.

Last year, as part of a long running High Court Case, the eight firms issued an unreserved apology for their part in the vetting system and the impact it had had on the job prospects and personal lives of those involved.

'Kicking and screaming'

Unite general secretary Len McCluskey said the scale of the damages underlined the "gravity of the misdeeds" of the companies involved.

"The sums to be paid out go a considerable way to acknowledge the hurt, suffering and loss of income our members and their families have been through over many years," he said.

Howard Beckett, the union's legal services director, said the companies involved "had to be dragged kicking and screaming to make unprecedented admissions of guilt" in October last year.

"In addition to financial compensation, admissions of guilt and formal apologies, the companies have agreed, as a result of this litigation, to issue guidance to site managers to ensure blacklisting is not occurring on a local level," he said.

Tim Roache, GMB general secretary said the companies involved thought they were above the law: "Finally they have been held to account in public and at great cost to them financially and reputationally. Government and employers' organisations must never forget this sordid episode."