Wrongly declared irregular? Don't count on 10% — the Council calculates your 'lost chance', and here it landed at 90%
The Council of State awards BV Rezuni 22,695.30 euros in restitution damages (90% of 10% of its offer price) after an earlier annulled award, because the flat-rate 10% rule does not automatically apply and the chance of being awarded the contract is concretely estimated.
What happened?
In 2020, the municipality of Uccle launched a simplified negotiated procedure with prior publication for repairing the cobblestone paving of Gendarmenlaan — price as the sole award criterion. Ten bidders submitted offers; BV Rezuni was the lowest at 252,170 euros (excl. VAT). On the submission deadline day (23 November 2020), the municipality published a rectification for post 16: the Dutch description had to specify 'sawn and flamed porphyry cobblestones'. Four bidders (including Rezuni) had already submitted and did not take the rectification into account. Their offers were declared irregular; the contract was awarded on 22 December 2020 to NV Colas for 301,031.71 euros. Judgment 254,394 (6 September 2022) annulled that award: the rectification was published on the deadline day itself, violating the principles of equality, transparency and proportionality. The current judgment addresses Rezuni's claim for restitution damages. The Council rules that article 16, third paragraph, of the Legal Protection Act (flat 10%) does not apply: it only applies to open and restricted procedures, and Rezuni cannot prove it would have been the lowest regular offer (its post-16 price did not account for the 'sawn and flamed' requirement, so its original price cannot serve as reference). Instead, the Council applies the lost-chance method under article 11bis of the Coordinated Laws on the Council of State. Even if Rezuni's price for post 16 were raised to the average of the regular offers (from 20,100 to 52,732 euros), its total would be 284,802 euros — still lower than Colas's 301,031.71. The probability of being awarded the contract is estimated at 90%, with a small residual uncertainty (too high or too low adjustment by Rezuni or by the other irregular bidders V. and J.). Damages = 90% × 10% × 252,170 = 22,695.30 euros, plus compensatory interest from 22 December 2020 and additional procedural costs.
Why does this matter?
For bid managers wrongly declared irregular: restitution damages are realistic, but the flat 10% rule is not automatic. The Council makes a concrete probability calculation — which can reach 90% with a clear price gap to the winner. For contracting authorities: a late rectification not only triggers an annulment but also substantial damages plus years of interest.
The lesson
If your offer is wrongly declared irregular: claim restitution damages and build your lost-chance argument concretely. Hypothetically adjust your total price (original price + plausible adjustment for the contested post to the average of regular offers) and compare with the winner. If you remain cheaper, that supports a high probability (up to 90%). Don't count automatically on the flat 10% — it requires undisputed proof that you were the lowest regular offer. As contracting authority: publish rectifications well before the deadline (and extend the period), and motivate irregularity findings explicitly.
Ask yourself
Your offer was declared irregular following a rectification or interpretation issue. Was there at least 4 days between the rectification publication and the submission deadline, with an extension for those who had already submitted? If not, your annulment ground is strong and a subsequent restitution damages claim is realistic. Don't rely on the flat 10% — build your lost-chance evidence with a hypothetical total price calculation.
About this database
The Council of State (Raad van State / Conseil d'État) is Belgium's supreme administrative court. In disputes over public procurement — from contract awards to tenderer exclusions — the Council of State is the final arbiter. The rulings in this database are summarised by TenderWolf in plain language, with practical lessons for tenderers and contracting authorities. View all rulings →