There is no necessary connection between receiving a lawyer's letter and being sued. Receiving a letter from a lawyer does not mean that you will be prosecuted. It depends on the other party's decision. After receiving the infringement warning letter or complaint from the patentee, the parties concerned should first take it seriously and then carefully distinguish it. If you don't do it yourself, you can reply and explain, but you must have corresponding evidence. If you do it yourself, you should carefully analyze whether the infringement is established.
legal ground
Article 1 19 of the Civil Procedure Law
The prosecution must meet the following conditions: (1) the plaintiff is a citizen, legal person and other organization that has a direct interest in the case;
(2) Having a clear defendant;
(3) Having specific requests, facts and reasons;
(4) It falls within the scope of civil litigation accepted by the people's court and is under the jurisdiction of the sued people's court.