A 'required option' rules your bid out, an 'allowed option' does not — and what the tender does not impose as a minimum, bidders are free to limit
The Council of State dismisses Siemens Mobility's extreme-urgency challenge to the award of the Hermelijn tram midlife revision to CAF (76.75 vs 70.94 out of 100): CAF was free to limit its corrosion treatment to 20 m² of light rust per tram and 3 cracks because the tender set no minimum surface area, free to overlap its study and prototype phases because the tender only required a 40-day gap between document submission and prototype start, and free to offer an incomplete anti-collision system because that was an 'allowed' (not 'required') option — and Article 56 § 2 of the Royal Decree on special sectors 2017 only sanctions the option itself in that case, not the base bid.
What happened?
De Lijn launched a framework contract for the midlife revision of about 125 MGT-6 'Hermelijn' trams running in Antwerp, Ghent and on the Belgian coast. Framework agreement of 8 years, renewable three times by 2 years. Procedure: negotiated procedure with prior call for competition (special sectors). Tender PG 1674-00531/PR 2020-008. Award criteria on 100: price (50), technical quality (40, broken into 'technical design and form' 5, 'sustainability and recyclability' 5, 'proposed working methods' 30), additional warranty (10). A mandatory site visit was required at the Antwerp (one-way) and Ghent (two-way) maintenance depots. Five operators applied, four were selected to bid. After several negotiation rounds and five successive refined versions of the tender, BAFOs were submitted and opened on 3 October 2022. One bid was declared irregular; two — Siemens Mobility and CAF — were found regular. Final ranking: Siemens 70.94 (price 39.19 + technical 27.5 + warranty 4.25), CAF 76.75 (price 50 + technical 16.75 + warranty 10). On 18 January 2023 De Lijn's board awarded to CAF. On 7 February 2023 Siemens filed an extreme-urgency challenge on three branches. First branch — corrosion treatment. CAF had expressly limited its corrosion approach in its bid: light rust up to 20 m² of exterior surface per tram (according to Siemens only 10% of the 206 m² total exterior), heavy rust up to three medium cracks of 25 mm per vehicle, no treatment of the interior surface (260 m²), exclusion of structural repairs, but a 10%-hour buffer for exceptional rust. Siemens argued this was a substantial irregularity: corrosion treatment is an essential part of the contract, and such a limitation would compromise comparability and equal treatment. The Council disagrees. Under 'minimum requirements', corrosion treatment is mentioned only once (pt 1.05.2): processes must be secured 'according to applicable standards and railway specifications and demonstrated with the necessary certificates' — a requirement that CAF meets. The tender sets no minimum curative treatment surface. De Lijn explains this was a deliberate choice 'given the technical impossibility of defining corrosion as a minimum requirement'. The site visits allow bidders to assess the actual condition themselves and tailor their approach. The proposed method is then evaluated under sub-award criterion 3.3, where the authority looks at added value vs minimum requirements. CAF received 'added value'; Siemens 'significant added value'. The assessment is reflected in the score — not in CAF's regularity. The branch fails. Second branch — study/prototype overlap. Pt 2.08.3.2 of the tender requires the study-phase documentation set to be filed 'at the latest forty (40) calendar days prior to the start of the prototype execution'. Siemens reads this as a strict separation with a mandatory waiting period. CAF foresees in its bid that 'further adjustments to the study can be made during prototype construction'. The Council follows CAF: pt 2.08.3.2 merely requires a 40-day gap between submission of the documentation set and prototype start — and CAF foresees 2.5 months between end of study (after 6 months) and start of the first prototype (after 8.5 months), well over 40 days. Pt 2.08.3.3 even states that the prototype documentation set is 'an improved version' of the study-phase one, with additions 'based on actual execution of one or two prototypes'. So the tender itself anticipates post-study adjustments during execution — no strict separation. De Lijn notes that CAF gains no pricing advantage, since its study team must remain available longer. Branch not serious. Third branch — anti-collision system. Pt 3.10.5 of the tender describes an 'allowed option' for a tram collision avoidance system with as minimum requirement: 'in a second phase (late or no driver reaction) the system intervenes with automatic electrical/emergency braking'. Siemens, the original maker of the Bosch anti-collision system, argues that CAF's offer does not include a software adjustment to the Siemens tram control software required for the automatic braking — only Siemens can supply it. Pt 1.03.4 of the tender states that 'non-compliance with the minimum requirements entails the substantial irregularity of the bid'. The Council compares this with Article 56 § 2 of the special-sector decree: for a required option, non-compliance makes both the option and the base bid substantially irregular; for an allowed option, non-compliance only affects the option, not the base bid. Pt 1.03.4 covers both. The sentence about 'substantial irregularity' can be read in line with Article 56 § 2, limited to required options. When a tender is written, it must be assumed that the authority exercises its powers consistently with legislation — the Council gives priority to that reading. Since Siemens does not dispute that the anti-collision system is an 'allowed' option, non-compliance with its minimum requirements does not entail the irregularity of CAF's base bid. Branch fails. Conclusion: no serious branch. Challenge rejected. Siemens pays 200 EUR roll fee + 24 EUR contribution + 770 EUR procedure indemnity to De Lijn. CAF pays the 150 EUR intervention fee.
Why does this matter?
This ruling is a three-in-one user manual for bid managers and contracting authorities. First lesson: a minimum requirement exists only when it is qualified as such, or when tender provisions are expressly designated as 'substantial' within Article 74 § 1 of the decree. If a tender 'wishes' something or describes how a bidder should approach a topic, the bidder is free to fill that in — and it will be assessed via award criteria, not via regularity. A competitor who thinks a rival has limited itself too much must challenge it in the assessment of added value, not as a ground for exclusion. Second lesson: 'X must be filed no later than 40 days before Y' is a minimum deadline for X, not a minimum duration between X and Y, and certainly not a ban on overlap within Y. Read tender clauses literally and in conjunction with other clauses — other provisions can show that later updating remains possible. Third lesson, and probably the most important: the distinction between 'required options' and 'allowed options' is no formality. Article 56 § 2 (classic sectors: identical Article 48 § 2 of the 18/04/2017 decree) provides that non-compliance with minimum requirements of a required option taints the entire base bid, while for an allowed option it only renders that option irregular. A general tender clause stating that 'non-compliance with minimum requirements leads to substantial irregularity' is read by the Council consistently with this decree provision: limited to required options. For a bid manager: if your rival fills in an 'allowed option' incorrectly, you do not buy any exclusion — you only affect its score on that option. For an authority: if you really want a functionality to be mandatory, classify it as a 'required' option or integrate it into the base description of the contract. 'Allowed' is for the bidder a safe playing field.
The lesson
When you receive or draft a tender, run three checks for each technical element: (1) Is it designated as 'minimum requirement' or as 'substantial' within Article 74 § 1? Otherwise, the bidder decides its own approach and it is weighed through award criteria. (2) For an option: is it classified as 'required' or 'allowed'? For an allowed option, non-compliance with minimum requirements only costs that one option, not the base bid. (3) For timing clauses: 'at the latest 40 days before the start of X' is a minimum deadline for submission — not a prohibition on overlap or further adjustments during X, unless other tender clauses expressly prohibit it.
Ask yourself
For every bid you analyse (your own or a competitor's): can you classify each critical aspect — required minimum requirement, non-required description (award criterion), required option, allowed option? And for each timing clause: can you tell whether it is a minimum, maximum or strict deadline? If you cannot recite this classification cold, you are almost certainly mis-estimating the regularity risk of your bid (or your chances of overturning a rival's).
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 →