If the patent formula is modified, it means that the product no longer meets the scope of patent protection, so marking the patent number on the product packaging may mislead consumers and cause unnecessary disputes. In addition, marking the patent number may also be considered as fraud and needs to be handled with caution.
If the applicant needs to modify the technical scheme in the patent application, it needs to apply to China National Intellectual Property Administration for modification under the condition of ensuring that the actual production is consistent with the patent formula. After the amendment application is approved, the patent number can be marked on the product packaging.