In 2023, 10 UK-based construction firms were found to have broken the law by entering into illegal arrangements to rig bids for demolition and asbestos removal contracts.



The wrongdoing took place between January 2013 and June 2018. It related to 19 contracts together worth over £150 million and affected both public sector and private sector clients with sites at the Metropolitan Police training college, the former Bow Street Magistrates Court, Selfridges (London) and Oxford University, among others.



On at least one occasion each, the firms colluded to submit proposals that were designed to lose the tender by putting forward a bid that was deliberately high or offering a poorer service. This practice is known as ‘cover bidding’.



Cover bidding can result in customers paying higher prices or receiving lower quality services or slower delivery. Those involved in such wrongdoing manipulate the tender process at the expense of the client and end payer which, in the case of public sector projects, is the taxpayer. Fair dealing businesses are also denied a level playing field to compete.



The ‘winning’ supplier knows they don’t face genuine competition so there is less incentive to offer the best deal or true value for money. It is a serious form of illegal conduct.  In this case, compensation payments were sometimes given by the ‘winners’ to the ‘losers’, and the real reasons for these payments were disguised.



The 10 businesses were fined over £60 million in total, and 4 directors have been held personally to account and disqualified from acting as directors for nearly 25 years in total.

What happened

Evidence of wrongdoing – cover bidding and compensation payments



The evidence in the case included emails, text messages and annotations found in notebooks, as well as explanations from individuals involved, showing illegal cover bidding and compensation payment agreements.



One example of the cover bidding involved a firm providing a rival with a copy of its tender pricing document, and instructing it to “go some 8% to 10% above this…”  and “[go in] longer on your program – ours is 44 wks.” The same firm then also provided a different rival with its pricing document but with similar instructions, namely that it “go some 10% to 12% above this.”



In another example, one firm told another that its bid was “far too close” and that “in short your number needs to increase substantially and ours has to decrease.”

Compensation payments



5 of the firms, on at least one occasion each, were involved in arrangements by which the designated ‘losers’ of the contracts were set to be compensated by the winner. The value of this compensation, and how it was implemented, varied but was higher than £500,000 in one instance. Some firms produced false invoices to hide this part of the illegal behaviour.



Examples of evidence of compensation payments included an extract from a notebook belonging to one company director found on the hard drive of a rival director  that set out a list of projects and noted certain monies ‘owed’, such as Lots Road Power Station with the note: ‘‘Lotts RD 100k owed.” 



An extract from another notebook set out a list of projects with monetary figures and the names of contractors next to them. This was later described as a ‘scorecard’ or a ‘slate’ of agreements related to cover bidding, and compensation given by the ‘winning’ supplier to the agreed ‘losers’ in the cover bidding arrangement.

How this broke the law



Discussing and agreeing with competitors what price you will submit for a bid or what level of service or timeframe you will provide is illegal. So is giving and accepting compensation payments for the wrongdoing. 



The businesses did not operate independently of each other. Through regular contact they co-operated in relation to bids for their own advantage, instead of competing for the benefit of customers.

Lessons from this case



Never agree with a competitor to submit or alter a bid to lose a tender so a rival can ‘win’ and never accept a compensation payment for doing so.



Never agree with rivals not to compete for customers or business.



Company directors must lead by example. They have personal responsibility for ensuring that the companies they lead comply with the law and director disqualification is a serious risk. The CMA secured the disqualification of four directors of firms involved in the unlawful conduct in this case.



The CMA has sophisticated means of tracking illegality and capturing evidence of secret unlawful activity – this was an intelligence-led case.

Benefits of co-operating with an investigation



If a company is the first to report being part of a cartel before the CMA is investigating and fully co-operates with an investigation, it can benefit from immunity from fines and will not be excluded from public procurement or appear on the central debarment list for that cartel activity (a new risk following changes to the procurement regime in the UK that came into force in February 2025). Also, its co-operating employees and directors can avoid criminal prosecution and director disqualification. Even after an investigation has started, businesses can still benefit from reduced fines through our leniency programme. In this case, 2 of the businesses did this and they benefited from a reduction in their fines.



Individuals may also be eligible for immunity from prosecution and director disqualification if they come forward independently and cooperate with the investigation.



If you think you may have broken the law, we always recommend that you seek independent legal advice.



If you have information on other companies in your industry that may have been involved in an anti-competitive arrangement, report it to us; you may qualify for a reward.



For more information, including how best to report, visit our ‘Cheating or Competing?’ campaign page

UK Construction Firms Fined for Bid-Rigging: Key Takeaways

In 2023, the UK competition authority uncovered illegal bid-rigging activities involving ten construction firms, which manipulated the tender process for demolition and asbestos removal contracts between January 2013 and June 2018.

The firms colluded on 19 contracts worth over £150 million, affecting notable clients such as the Metropolitan Police training college and Oxford University. Their tactics included 'cover bidding', where they submitted intentionally high bids to ensure a rival would win.

This collusion not only inflated costs for clients but also compromised the quality of services provided. The firms involved were fined a total of over £60 million, and four directors faced disqualification for nearly 25 years.

Evidence of wrongdoing included emails, text messages, and notebooks detailing agreements on bid prices and compensation payments between the firms. In some instances, compensation payments exceeded £500,000, disguised through false invoices.

The case highlights the importance of compliance with competition law, emphasizing that discussing and agreeing on bid prices or service levels with competitors is illegal. Company directors are urged to lead by example to ensure adherence to legal standards.

Additionally, the competition authority encourages companies to report cartel activities, offering immunity from fines and prosecution for those who cooperate with investigations.



UK Construction Firms Fined for Bid-Rigging: Key Takeaways

Ten UK construction companies were fined over £60 million for engaging in illegal bid-rigging practices, impacting public and private sector contracts.