Therefore, Claim 4 does not conform to the provisions of the Patent Law. Since Claim 3 has quoted two claims, it cannot be used as the reference basis for other subordinate claims.
The central claim system is the "center" where claims can define invention-creation patents. The exact scope of protection is determined by the inventor's contribution to the technical progress in this field. The central claim system has been used for a long time in the United States and Britain. Germany and most other continental European countries still use it.
Extended data:
Subordinate claims have three functions. If we are aware of this, we can avoid many potential future problems in the writing process.
Role 1: The role of the application stage is limited to invention patents.
In the substantive examination of the invention patent, if the independent claim is not patentable, the examiner will examine the subordinate claim, without the need for the applicant to modify the independent claim. In this way, the review order is omitted, which saves time for both the examiner and the applicant.
Role 2: The role in the litigation stage.
Dependent claims have a narrower scope of protection due to the addition of new technical features, and at the same time the scope of protection is more clear and specific. In the process of patent litigation, the infringer may use the generality of independent claims as an excuse to avoid liability, and the existence of subordinate claims will make it easier for judges to judge tort liability.
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