The decision is the latest blow to the OFT’s assault on construction which saw 103 firms hit with fines totaling £129m in 2009 following a long-running probe into cover-pricing.

North Midland Construction also had its fine cut from £1.5m to £300,000 as AH Willis saw its £120,000 fine reduced to zero and GMI had its £1.8m fine scrapped.

The tribunal decided that “the OFT had not established on the balance of probabilities that the Appellants had committed either of the alleged infringements.”

The latest rulings mean that every contractor who launched an appeal against the OFT fines has seen them reduced by up to 94% or written-off completely.

The OFT is currently deciding whether to appeal against the rulings.