GCR, GMB and Ucatt have all agreed settlements, leaving only Unite members to fight a court case set to start on 9 May.

It is understood that 97 Unite members are yet to settle their claims against contractors Balfour Beatty, Carillion, Costain, Kier, Laing O’Rourke, Sir Robert McAlpine, Skanska UK and Vinci.

Some of the remaining claimants may yet settle before next month’s High Court case, with offers understood to have been made to all.

The companies made a full public apology in October 2015, which the three unions to have settled their claims all accepted on behalf of their members.

Now, the unions have accepted “fair and reasonable” financial settlements and agreed on a statement to be read in court.

In a statement, the group of defendants said: “These construction companies now 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.”

In February, 71 Ucatt members shared £5.6m in compensation for breach of the Data Protection Act, defamation and loss of earnings.

In total, around 650 union members are taking or have taken legal action against the eight firms over historic blacklisting.

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