ECOWAS Tenders Code 4. The Public Contracting Officer, shall upon request communicate to suppliers, contractors and service providers that have not been pre-qualified the grounds for their rejection within five (5) working days. 5. The procuring entity may require a supplier, contractor or service provider that has been prequalified to demonstrate again if selected its qualifications in accordance with the same criteria used to pre qualify it before concluding a contract. Section III: Two-Stage Bidding Article 42: Conditions and Procedures for two-stage bidding 1. The Public Contracting Officer may engage in contracting by means of two-stage bidding in order to obtain the most satisfactory solution to its procurement needs, when, as a result of the complex nature of the procurement or the need for performance criteria, it is not feasible to formulate detailed technical specifications for the goods or works or, in the case of services, to identify their characteristics. 2. Two-stage bidding may be preceded by prequalification proceedings conducted in accordance with Articles 39 to 41 above. 3. In the first stage of the two-stage bidding, bidders are invited to submit their technical proposals on the basis of a conceptual design or of performance specifications. The evaluation of the technical bids may require the contracting officer to revise the cost estimate of the project. In the second stage of the two-stage bidding, bidders meeting the qualification criteria and whose bid was found technically acceptable at the first stage, are invited to present final technical and financial proposals on the basis of the bidding documents revised as needed by the Public Contracting Officer. Section IV: Restricted Bidding Article 43: Conditions for Restricted Bidding 1. Restricted bidding is a procedure open only to bidders who have been directly invited by the Public Contracting Officer to submit a bid. 2. Restricted bidding may be conducted when the goods, works or services in question are available only from a limited number of entities, provided that the Public Contracting Officer solicits bids from all those suppliers, contractors or service providers meeting the criteria determined by the procuring entity. The Public Contracting Officer shall seek bids from a list of potential suppliers broad enough to ensure competitive prices, and such list to include all suppliers when there are only a limited number. Final Page 19