If your specifications ask for 'recent certificates from the manufacturer', you cannot later accept a supplier's own technical sheet
OTW required 'recent certifications' from the constructor for ZF gearbox oil, but awarded to WOLF OIL which only attached its own technical data sheet — the Council of State suspends with immediate execution: a contracting authority cannot loosen its own specifications after the fact.
What happened?
In June 2018 the Walloon public transport operator OTW launched a European negotiated procedure with prior competition for the exclusive supply of oils to the TEC bus group. Four lots, total estimated volume 750,000 litres over 4 years (1 December 2018 – 30 November 2022). Lot 2 covered oil for the automatic ZF gearboxes — estimated at 60,000 litres. The specifications stipulated: 'The oil offered shall be of type TUTELA TRANSMISSION ATF 120' AND 'It shall propose an oil meeting the requirements of the ZF gearbox manufacturer and shall attach to its offer recent certifications'. Five firms were shortlisted: BELUB, INGELBEEN-SOETE, TOTAL BELGIUM, WOLF OIL CORPORATION and ZF SERVICES BELGIUM. All five filed initial offers on 6 September, received a Best and Final Offer invitation on 13 September, and submitted BAFOs on 18 September. On 17 October 2018 the board awarded lot 2 to WOLF OIL for €133,093.06 (kilometric cost over 4 years). The ranking: WOLF OIL 75/80, BELUB 62.56/80 (€161,845.96), TOTAL 59.32, INGELBEEN-SOETE 48.89; ZF SERVICES BELGIUM was found irregular. BELUB filed an extreme-urgency application on 2 November and argued: WOLF OIL did not attach a ZF certification; its products are not on the official quarterly list of ZF-approved lubricants (TE-ML 14 or TE-ML 20); its offer was therefore substantially irregular and should have been rejected. OTW defended itself with three arguments: (1) WOLF OIL had submitted its own technical sheet which explicitly confirms compatibility with ZF TE-ML 14C and 20C; (2) the specifications did not impose this requirement 'on pain of nullity'; (3) requiring a manufacturer's certification would be disproportionate — obtaining one is slow and costly, and a real certification depends on the supplier's active request, so compatible oils without certification would be excluded. OTW even called the requested modality 'préférentiel', not exclusive. The Council of State, presided by Imre Kovalovszky, dismantles each defence. The specifications combine two conditions: oil 'of type TUTELA TRANSMISSION ATF 120' AND meeting the manufacturer's requirements. From this dual condition it follows that 'of the type' is not enough — the second condition adds an autonomous requirement. By imposing 'recent certifications', OTW determined the proof modality itself. The wording is unambiguous and does not appear to allow alternatives — all the more so because the specifications do not even spell out which manufacturer's requirements the oil must meet, which is precisely why the certification document is needed. The required modality is therefore not 'preferential' but exclusive. It is also not unreasonable that OTW required this: the official ZF list is precisely a reliable form of proof. WOLF OIL admitted having no ZF certification and only referred to its own technical sheet; its products are not on the TE-ML 14 or TE-ML 20 list. By declaring the offer regular, OTW failed to apply its own specifications. The disproportionality defence is irrelevant: the specifications do not provide an alternative modality, and neither the award decision nor the evaluation report explains why a deviation was permitted here. Most decisive of all: BELUB showed at the hearing, uncontested, that an 'self-certified' product such as WOLF OIL's has a different price structure from a product that has gone through real certification testing — the latter being more expensive. By failing to require a certification document, OTW thus granted a discriminatory advantage to WOLF OIL at the expense of bidders (like BELUB) who had followed the rule. The plea is serious. Suspension ordered with immediate execution.
Why does this matter?
This judgment goes to the most fundamental principle of public procurement: patere legem quam ipse fecisti — those who make the rules must follow them. It shows that a contracting authority cannot retroactively soften its own specifications by invoking 'proportionality' or 'competition promotion'. For contracting authorities: anything you write as a proof modality is exclusive unless you explicitly allow alternatives. Want flexibility? Write 'a certification or any equivalent proof' — don't wait until the procedure is running to figure that out. For bidders: in grey zones, your best defence is to follow the strict requirement and flag it in your offer. If you stick to the rules and see competitors bypass them, you have a strong ground — especially if the price of strict compliance is demonstrably higher than the deviating offer. The discrimination argument was decisive here: WOLF OIL could underbid precisely because it had skipped the more expensive certification.
The lesson
When specifications impose a specific proof modality ('certifications from the manufacturer', 'certification by an independent body', 'report drawn up to standard X'), treat it as exclusive. As contracting authority in doubt: rewrite the specifications with explicit alternatives ('or any equivalent proof'); failing to do so and accepting other documents afterwards risks suspension. As bidder in doubt: provide exactly what is asked — no alternative technical sheet, brochure or self-declaration — and watch what competitors miss during the standstill period. The argument 'the specifications carry no nullity sanction' turns out to be worthless when the proof modality touches a substantive specification and its absence yields a price advantage.
Ask yourself
Your specifications ask for 'recent certificates of X' or 'certification under Y'. A bidder instead provides a self-declaration or a brochure. What does your evaluation report say? (1) A reasoned finding that this alternative is equivalent — based on something the specifications allow? Or (2) implicit acceptance without reasoning? In the second case you risk suspension with immediate execution, especially if the deviating bidder underbids those who provided the requested proof — that price gap is itself evidence of a discriminatory advantage.
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 →