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
Claims having Overlapping Features but Progressively Adding New Features
Unity of Invention Exists – Example 17
10.37 Example 17
Claim 1: A display with features A + B.
Claim 2: A display according to claim 1 with additional feature C.
Claim 3: A display with features A + B with additional feature D.
Unity exists between claims 1, 2, and 3. The special technical feature common to all the claims is features A + B.
No Unity of Invention (a priori) – Examples 18 to 20
10.38 Example 18: Common Structure
Claim 1: A process of manufacture comprising steps A and B.
Claim 2: Apparatus specifically designed for carrying out step A.
Claim 3: Apparatus specifically designed for carrying out step B.
Unity exists between claims 1 and 2 or between claims 1 and 3. There is no unity between claims 2 and 3 since there exists no common special technical feature between the two claims.
10.39 Example 19: Common Structure
Claim 1: A process for painting an article in which the paint contains a new rust inhibiting substance X including the steps of atomizing the paint using compressed air, electrostatically charging the atomized paint using a novel electrode arrangement A and directing the paint to the article.
Claim 2: A paint containing substance X.
Claim 3: An apparatus including electrode arrangement A.
Unity exists between claims 1 and 2 where the common special technical feature is the paint containing substance X or between claims 1 and 3 where the common special technical feature is the electrode arrangement A. However, unity is lacking between claims 2 and 3 since there exists no common special technical feature between them.
Sometimes, claims contain ranges that overlap with the ranges of other claims. Determination of unity of invention in these cases requires careful consideration. The lack of unity observation will depend on the facts of the case, and care should be taken that an objection is not raised on the basis of a narrow, literal or academic approach, as warned against in paragraph 10.04. Similarly, as stated in paragraph 10.05, International Authorities may have differing practices when approaching the following example.
Claim 1: Carbon steel comprising 0.10-0.40% manganese.
Claim 2: Carbon steel comprising 0.60-1.65% manganese.
Claim 3: Carbon steel comprising 0.50-0.90% manganese.
The specification notes that –
- Carbon steel comprising 0.10-0.40% manganese results in reduced oxidation at high temperatures.
- Carbon steel comprising 0.60-1.65% manganese results in improved electrical conductivity.
- Carbon steel comprising 0.50-0.90% manganese results in improved strength while surprisingly drastically improving ductility.
It is common general knowledge that carbon steel contains manganese. Claims 1 and 2 and claims 1 and 3 lack unity a priori but unity of invention exists between claims 2 and 3. However, if prior art existed teaching or suggesting any part of the overlapping range within 0.60-0.90% manganese in carbon steel resulting in improved electrical conductivity and/or improved strength while surprisingly drastically improving ductility, then unity would not exist a posteriori between claims 2 and 3.