PCT International Search and Preliminary Examination Guidelines

PART III EXAMINER CONSIDERATIONS COMMON TO BOTH THE INTERNATIONAL SEARCHING AUTHORITY AND THE INTERNATIONAL PRELIMINARY EXAMINING AUTHORITY

Chapter 10 Unity of Invention

Examples Concerning Unity of Invention

10.20 The application of the principles of unity of invention is illustrated by the following examples for guidance in particular cases.

Determining special technical features is addressed in paragraphs 10.01 to 10.10, above. It is recognized that Authorities may differ in determining which features are special technical features on a case by case basis based on how the Authority determines whether any shared technical features make a contribution over the prior art. Except as otherwise noted, the following examples proceed on the basis that the shared technical feature is, as determined by the Authority, a special technical feature. The examples below are provided in respect of the following scenarios:

(i) Different aspects of the invention claimed (method, apparatus, product etc.): Examples 1 to 16 (see paragraphs 10.21 to 10.36);

(ii) Claims having overlapping features but progressively adding new features: Examples 17 to 20 (see 10.37 to 10.40);

(iii) Complementary forms of the invention (e.g. receiver and transmitter): Examples 21 to 23 (see paragraphs 10.41 to 10.43);

(iv) Alternative forms of an aspect of the invention (varying solutions to the same problem): Examples 24 to 39 (see paragraphs 10.44 to 10.59);

(v) Dependent claims adding substantial feature which diverge from the inventive concept (lack of unity a posteriori): Example 40 (see paragraph 10.59A);

(vi) Lack of unity of invention in a single independent claim: Examples 41 to 42 (see paragraphs 10.59B and 10.59C);

(vii) Complex claim sets with overlapping features: Example 43 (see paragraph 10.59D); and

(viii) Examples of the use of the minimum reasoning: Examples 44 to 48 (see paragraphs 10.59E to 10.59J).