What if buying and selling patents is routine?

First of all, we should pay attention to 1. Pay attention to whether the transferor illegally occupies the patent and whether the patent is owned by * * * 2. The transfer of the patent must be registered and announced by the Patent Office. 3. As the patent may be declared invalid, we should clearly stipulate the legal consequences and possible liabilities for breach of contract after the patent is invalid in the contract, and pay attention to the years of patent protection. 4. The name, nature, content and ownership status of the patent need to be clearly defined in the contract. In addition, if it can be determined that the patentee is malicious, applies for a patent for an invention-creation that he knows should not be granted a patent, and transfers or licenses the patent to others, the patentee is liable to compensate you for your losses according to the law, that is, you can take them to court according to law.