1. Pharmaceutical companies provide samples or samples free of charge, and do not issue invoices. These samples are used for publicity and promotion purposes and do not involve actual transactions.
2. When a pharmaceutical company donates drugs to a charity or public welfare organization, it will not issue an invoice immediately. Relevant parties will provide relevant vouchers and documents to meet relevant regulations and tax requirements.
3. Drug sales involve special authorization or agreement, and delay in issuing invoices is allowed. In specific hospital procurement projects, a special agreement will be reached with the hospital to clarify the time and method of invoicing.