BT-50 et al. - notion of "second stage"

A contracting authority in Belgium submitted some questions regarding the wording of BT-50 “The minimum number of candidates to be invited for the second stage of the procedure.”

The CA is conducting a competitive procedure with negotiation (2014/24/EU) and is using notice subtype 16. They replied “no” to BT-661 (“There is a maximum number of candidates to be invited for the second stage of the procedure.”) since all participants will be invited to submit a tender.

This forces them to fill in BT-50 with the minimum number of candidates that will be invited to the second stage of the procedure. The problem for them lies with this notion of “second stage”. As specified in art. 29 §6 of the directive, “Competitive procedures with negotiation may take place in successive stages in order to reduce the number of tenders to be negotiated by applying the award criteria specified in the contract notice, in the invitation to confirm interest or in another procurement document. In the contract notice, the invitation to confirm interest or in another procurement document, the contracting authority shall indicate whether it will use that option.”

The CA states that the notion of “second stage” is not apt, since a negotiated procedure can consist of multiple stages and therefore the number of candidates could be limited in either of those stages, not necessarily in the second one.

Hence their/our questions

• How to interpret this notion of second stage?
• Whether the wording of BT-50 (as well as BT-51 and BT-661) should be revised?
• Whether some other BT's / business logic should be foreseen for procedure types consisting of multiple stages?