Next the examiner should start the search process by formulating a search strategy, i.e. a plan consisting of a series of search statements expressing the subject of the search, resulting in sections of the documentation to be consulted for the search. In its initial phase, a search strategy will contain one or more combinations of the basic components mentioned in B‑III, 2.2. The search process should be interactive and iterative in the sense that the examiner should reformulate his initial search statement(s) according to the usefulness of the information retrieved (see B‑III, 1.1, and B‑IV, 2.4 and B-IV, 2.6). When using classification groups, the examiner should select the classification groups to be consulted for the search, both in all directly relevant fields and in analogous fields.
The examiner should consider, when appropriate, also consulting other classification (e.g. FI) or indexing (e.g. F-terms) schemes. Consultation of colleagues in a similar technical field or in fields possibly related to the content of the application should also be considered (see B‑I, 2.1).
When in doubt about the appropriate fields in which to conduct the search, the examiner may request advice from the appropriate classification expert.
Usually various search strategies are possible, and the examiner should exercise his judgement, based on his experience and knowledge of the available search tools, to select the search strategy most appropriate to the case in hand. He should give precedence to search strategies yielding sections of the documentation in which the probability of finding relevant documents is highest. Usually the main technical field of the application will be given precedence, starting with the basic components (see B‑III, 2.2) most relevant to the specific example(s) and preferred embodiments of the claimed invention. In considering whether to extend the search to other less relevant sections of the documentation, the examiner should always take account of the search results already obtained.