Sometimes an offer may be of a continuous nature and is known as Standing Offer. A standing offer is in the nature of a tender. An advertisement inviting tenders is not an offer but a mere invitation to offer. It is the person submitting the tender to supply goods or services who is deemed to have made the offer. When a particular tender is accepted or approved, it becomes a standing offer. The acceptance or approval of a tender does not, however, amount to acceptance of the offer.
It means that the offer will remain open during a specific period and that it will be accepted from time to time by replacing specific orders for the supply of goods. Thus each order placed creates a separate contract.