How do kind codes differ between PCT and U.S. national stage applications?
Kind codes for PCT (Patent Cooperation Treaty) applications and U.S. national stage applications differ in their usage and meaning. The MPEP 901.04(a) provides the following information:
For PCT applications:
- “A1” – PCT application published with the international search report
- “A2” – PCT application published without the international search report
- “A3” – PCT search report published separately from the application
For U.S. national stage applications:
- “A” – Patent Application Publication
- “B1” – First U.S. Patent Grant
- “B2” – Second U.S. Patent Grant (reexamination)
Understanding these differences is crucial for accurately identifying and interpreting patent documents from different sources and stages of the patent process.
To learn more: