Is it infringement to improve other people's patented products?

1. If "improvement" in the text means "adding new features or functions", it constitutes infringement. Because judging patent infringement is a universally applicable principle, or the principle of all factors. If your improvement is based on someone else's patent, that is, you add some features and functions to someone else's patent, then the improved product still contains all the features of the previous patent except the added features, which satisfies the principle of total factor. In short, the previous patent was A+B+C. You use A+B+C or A+B+C+.

2. If your improvement is "reducing or replacing some features or functions", it does not constitute infringement. Of course, the substitution here should exclude equivalent infringement.

3. Therefore, on the basis of the improvement of existing patents, whether the improved product infringes depends on the comparison between the final product and the basic patent, that is, whether it conforms to the universal coverage principle of patent infringement judgment.

4. Continue to improve on the basis of existing patents. The improved scheme can apply for a patent alone, which is expected to be authorized. However, the implementation of the patent is restricted by the previous basic patents, which may constitute the conditions for cross-licensing.