How does a Supplementary International Search differ from the main international search?

A Supplementary International Search (SIS) differs from the main international search in several key aspects:

1. Optional nature: SIS is an optional service, while the main international search is mandatory for all PCT applications.
2. Timing: SIS can be requested up to 22 months from the priority date, while the main search is conducted earlier in the process.
3. Searching Authority: As per PCT Rule 45bis.9(b), The International Searching Authority carrying out the international search under Article 16(1) in respect of an international application shall not be competent to carry out a supplementary international search in respect of that application.
4. Scope: SIS may have limitations on subject matter or number of claims searched, as outlined in PCT Rule 45bis.9(c).
5. Unity of invention: SIS will only cover one invention or group of inventions having unity of invention, without the option to pay additional fees for searching multiple inventions.

These differences allow the SIS to complement the main international search, providing a more comprehensive prior art search for PCT applicants.

To learn more:

• Supplementary International Search
• SIS
• PCT
• International Search
• Patent Search