The seller shall deliver relevant documents and materials other than the documents for withdrawing the subject matter in accordance with the agreement or transaction practices. The documents and information generally include commercial invoices, transportation documents, insurance certificates and agreed technical information, etc., which are the incidental obligations of the seller.

If the contract does not clearly stipulate the order of delivery of invoices and payment, the buyer and the seller shall perform at the same time, but the buyer's main obligation is to pay the price, and the seller's main obligation is to deliver the goods, and the issuance of invoices is only for Incidental obligations of the seller. If the seller has fulfilled its main obligations under the contract and delivered the goods, the buyer no longer has the right to defend against simultaneous performance and may not refuse to pay the price on the grounds that the seller has not issued an invoice. Unless the contract clearly stipulates that the seller should pay the invoice first, the buyer cannot exercise the right of first performance defense and require the seller to pay the invoice first and then pay the purchase price.

For one party’s failure to pay the invoice, can the other party refuse to pay the purchase price on this basis?

The first opinion is that the plaintiff, as the payee, has the obligation to issue invoices, but the plaintiff has not delivered the invoice, and the defendant has the right to refuse to pay for the goods. According to the "Invoice Management Measures of the People's Republic of China" (hereinafter referred to as the "Invoice Management Measures"), the payee for business operations shall issue an invoice to the payer. Therefore, the plaintiff has not yet delivered the corresponding invoice to the defendant, which has violated its legal obligation to issue invoices in a timely manner. In addition, the defendant's defense on this ground is also in line with Article 66 of the Contract Law of the People's Republic of China (hereinafter referred to as the "Contract Law"), which states that "if the parties owe each other debts and there is no order of performance, they shall be performed at the same time." "One party has the right to refuse the other party's performance request before the other party performs it. When the other party's performance of debts does not meet the agreement, one party has the right to refuse its corresponding performance request" does not constitute a breach of contract.

Second opinion It is believed that the plaintiff's failure to issue an invoice cannot be used as a defense for the defendant's refusal to pay for the goods. The author also agrees with this view. First, the relationship between the principal obligations and the incidental obligations in the contractual relationship should be clarified. The principal obligations are inherent in a certain contractual relationship. , necessary, and the basic obligations that can determine the type of contractual relationship; incidental obligations refer to obligations based on the principle of good faith and to ensure the realization of the creditor's payment interests. They are stipulated or statutory notices, other than the subject matter, price and other main terms of the contract. Obligations such as assistance and confidentiality have the function of balancing personal rights and social rights and pursuing substantive justice. The relationship between the two is subordinate. When one party fails to perform the main payment obligation, the other party has the right to refuse to perform its own obligations. , and if one party violates the incidental obligation, it has already fulfilled the main payment obligation, the other party shall not invoke the right of simultaneous performance defense. It is worth noting that Article 66 of the Contract Law stipulates that. : "One party has the right to refuse the other party's corresponding performance requirements when the other party's performance of the debt does not meet the agreement." The debt agreed here should refer to the agreed principal payment obligation, rather than based on the principle of good faith stipulated in Article 60 of the "Contract Law" In addition, the right of simultaneous performance of defense is premised on the relationship between the parties to the contract, that is, the payment of consideration in the bilateral contract. One party may refuse to pay before the consideration is paid, and the incidental obligations do not belong to consideration. The subordination of the obligation to pay determines its function of promoting the realization of the obligation to pay. In this case, the parties did not agree to issue an invoice in the contract. Therefore, in accordance with the relevant provisions of Article 60 of the Contract Law and the Measures for the Administration of Invoices, invoices were issued. The invoice is an incidental obligation. Since this obligation is not a contractual obligation relative to the defendant's payment for the goods, the defendant cannot use the plaintiff's failure to perform this obligation as a defense to refuse to perform its contractual obligations. The payer shall bear corresponding liability for breach of contract.

After the payee makes the payment, the payee may request the payee to issue an invoice. If the payee refuses to issue an invoice, the payer may report to the tax department or file a lawsuit against the payee. The payer claimed losses caused by failure to issue invoices.