2. the feature of weight 2 is a+b.
3. The feature of weight 3 is A+B+CB+C.
If the right 3 directly refers to the right 1, then the range is a+c, of course, it is different.
Not necessarily. The scope of the independent claim is the largest, and the purpose of applying for the dependent claim is to make the patent right more stable, so as to avoid that the invention can not be effectively protected after the exclusive right is invalid in the subsequent invalid procedure; The second is to prevent others from choosing a small area to apply for a patent within the scope of their own invention and creation protection.
Therefore, the setting of right citation in the claims written by excellent agents is determined based on the above two considerations.