3.7 Independent and dependent claims 

The search carried out in the documentation to be consulted for the independent claim or claims must also cover all dependent claims (for cases not complying with Rule 43(2), see B‑VIII, 4). Dependent claims are ones which are restricted by all the features of the claim or claims on which they depend. So, where the subject-matter of an independent claim is novel, that of its dependent claims will also be novel (see, however, F‑VI, 2.4.3). When the patentability of the subject-matter of the independent claim is not in doubt after the search, there is no need to carry out a further search or cite documents for the subject-matter of the dependent claims as such (see, however, B‑II, 4.2(iii) and B‑XI, 1.2).

Example 1

An application relating to cathode ray oscilloscope tubes has an independent claim directed to specific means along the edge of the front of the tube for illuminating the screen and a dependent claim directed to a specific connection between the front and the main part of the tube. When searching in the parts of the documentation consulted for the illumination means, the search division will also look for material relating to the connecting means, whether in combination with the illumination means or not. But, if its search in these parts of the documentation does not cast any doubt on the patentability of the illuminating means, it will not continue the search on the connecting means in other parts of the documentation which are likely to contain material relevant to or dealing specifically with these connections.

Example 2

An application dealing with a pharmaceutical composition for treating nail infections has an independent claim relating to specific combinations of the active ingredients The patentability of this claim's subject-matter is not in doubt after the search, so there is no need to continue the search in relation to dependent claims dealing with the use of a specific volatile organic solvent as a carrier in the composition.