Searching by Kind Codes?

[K.]

I want to limit my searching using the kind code listed on the biblio page. What is the correct field to search? There is a KC field but it's not listed in the documentation and while the parser accepts it as valid, it never produces positive results.

[Iustin]

The correct field is IC
Example:
IC:A61K

[K.]

No, not the class code; a kind code, such as this.

WO2004012345A1

The last two characters are the kind code (A1).
Also sometimes known as publication code.

[Iustin]

There is no such field in the index.
Iustin

[K.]

Well the old search certainly had it, and the biblio's I see in the new search list the kind code as a separate field. The new parser accepts KC without complaint, but returns no hits. Please convey to your technical lead that if you are hosting national collections, that some nations use identical document numbers with different kind codes to refer to entirely different documents. Unlike WIPO, which sensibly uses unique document numbers.