2.2 Effectiveness and efficiency of the search 

The effectiveness and efficiency of any search for relevant documents (Rule 61(1)) depend on the degree of order which is inherent in, or which can be applied to, the searched document collection as it is this order that enables the search division to determine which parts of the documentation to consult. The basic means of creating order in a document collection are words, classification units, indexing codes or bibliographical links. The order can be permanent, as with indexing words or codes and classification symbols, or it can be created on demand by a search strategy judiciously using the basic means mentioned above to identify the parts of the documentation that are likely to contain material relevant to the invention. To ensure its resources are deployed as efficiently as possible, the search division, drawing on its knowledge of the technology in question and the available search tools, uses its judgement to omit parts of the documentation in which it is unlikely that any relevant documents will be found, for example parts containing documents from before the area of technology in question began to develop. Similarly, it only needs to consult one member of a patent family unless it has good reason to suppose that, in a particular case, there are relevant substantial differences in the content of different members of the same family (see B‑IX, 2.4).