According to Article 15 of the Contract Law, an invitation to offer, also known as an invitation to offer, refers to the expression of intention to expect others to make an offer to themselves.

Such as sending price list, auction announcement, tender announcement, prospectus, commercial advertisement, etc. It's an invitation to offer. However, if the content of a commodity advertisement conforms to the provisions of the offer, it shall be regarded as an offer. Because an invitation to offer is only an expression of the intention of others to make an offer to it, an invitation to offer can be sent to anyone who is not specific, and it does not need to be expressed in detail in the invitation to offer, and it is not binding on the inviter or the invitee.