The process would have been, approximately:
- Decide what is important for your train and write a specification.
- Publish an advertisement in the Official Journal.
- Send all responders a prequalification document inviting them to respond to specific questions and including the selection criteria that will determine how bidders are selected according to the answers.
- After the deadline for prequalification responses, select the prequalified bidders making sure the selection criteria are strictly followed. If properly done this will result in enough credible bidders to ensure competition but not so many that the process becomes unworkable.
- Send the prequalified bidders the full Invitation to Tender including the spec and the final selection criteria, which will be similar to the prequalification but hugely more detailed. Notify the others of failure to prequalify. Hold breath awaiting possible challenge.
- Assuming no challenge, await responses from bidders by deadline. Evaluate responses again, also paying attention to strict adherence to selection criteria. Possibly negotiate with a preferred bidder while keeping the others in reserve in case no agreement can be reached.
- Announce winning bidder. Wait for "standstill period" when other bidders can challenge. Sign contract.
The above is intended to ensure that all bidders compete on merit. If not strictly followed there is a strong chance of legal challenge from either unsuccessful bidders or the European Commission. In particular, requirements and selection criteria have to be based on genuine needs of the client, not things that are included to favour the selection of the supplier that the client really wants! These issues are likely to be at the root of the various battles arising from the Eurostar procurement.