It means "patent pending".
◎ Provide supplementary explanation:
The literal meaning of "patent pending" is "patent pending". According to the US patent law, a patent application must be filed before the related products can be marked as "patent pending". So when we see the label of "patent pending approval" on the product, we can conclude that the manufacturer has filed a patent application, but this situation is not 100% correct, because some manufacturers may make improper labeling, although Article 290 of the US Patent Law stipulates that improper labeling will be fined.