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Patent Document Authority Files

Reexamination Certificates file layout

The first field is eight positions and contains the "Document Number".

The second field is eight positions and contains the "Publication Date" in a YYYYMMDD format.

The third field is two positions and contains the patent "Kind of Document Code".

Example:

B5093617 20001219 B1
B4490209 20001219 B2
C5775534 20010102 C1
CD350855 20020108 C1
CRE33507 20020528 F1
C4940488 20020618 C2
BRE33209 19960116 F2
United States Patent and Trademark Office
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Last Modified: 7/4/2009 6:38:57 PM