A contracting authority is only permitted to use a limited tendering procedure (whereby no tender is called or suppliers are invited individually to submit a tender) for procurement in certain circumstances, such as:

• where an open or selective tender procedure was used but no tender was received;
• when the goods or service to be procured can only be supplied by a particular supplier for technical reasons, or for reasons connected with the protection of exclusive rights (such as intellectual property rights), or by reason of being a work of art;
• when (but only if it is strictly necessary), for reasons of extreme urgency brought about by events unforeseeable by the contracting authority, the goods or service cannot be obtained in time by means of the open procedure or the selective procedure; or
• when the service to be procured is an extension of an existing service, and where to obtain the service from a person other than the person who performed the existing service will result in the contracting authority obtaining a service not meeting its requirements of interchangeability with existing goods, installation or service.

Further, a contracting authority must not carry out limited tendering with a view to avoiding competition or protecting suppliers established in Singapore or otherwise in a manner which is discriminatory against any applicable supplier.

If a contracting authority allegedly violates the competitive bidding requirement, a supplier or bidder can bring a challenge before the Government Procurement Adjudication Tribunal ("Tribunal") for such alleged breach of duty by a contracting authority. Details are set out in Section 8 below.