In similarly-worded statements, both companies claim to have cooperated fully with the OFT in its investigations and are confident they both now comply with the Competition Act 1998.
Balfour Beatty Construction Limited, Balfour Beatty Refurbishment Limited, and Balfour Beatty Group Limited are all under investigation by the OFT for alleged infringements from 2000 onwards.
Balfour Beatty subsidiary Mansell Construction Services Limited is under investigation for alleged infringements from 19 December 2003, together with their current ultimate parent company Balfour Beatty plc. for alleged infringements involving Mansell prior to 19 December 2003, Mansell and its former ultimate parent company Mansell plc.
The OFT is looking at Carillion for alleged infringements by the Mowlem business, which Carillion bought in 2006.
Of the 112 companies the OFT is investigating, 37 immediately applied for leniency when the investigation began, which was prompted by a specific case in the East Midlands in 2004, although the investigation quickly spread throughout the country.
A further 40 companies applied for leniency when prompted by the OFT. Companies that apply for leniency may escape prosecution and be granted a reduction in the fine it could incur.
35 of the original 112 companies under investigation have not applied for leniency.
The OFT can impose fines of up to 10% of the company's turnover as a penalty for price-rigging offences.