U.S. Patent Document Kind Codes

The USPTO introduced new patent document kind codes, shown in Table 1, on January 2, 2001. Codes used prior to 2001 are shown Table 2. Patent offices use kind codes, which are defined under WIPO Standard ST.16, to distinguish between different types of patent documents. Kind code H is in the process of being phased out due to the cancellation in 2013 of the Statutory Invention Registration Program. Kind codes F, J, K and O were created in 2012-2013 as a result of provisions in the America Invents Act of 2011.

Table 1. U.S. Patent Document Kind Codes (as of Jan. 2, 2001)

Kind Code	Document Type	Note
A1	Utility application, first publication
A2	Utility application, second or subsequent publication
A9	Utility application, correction
B1	Utility patent, no pre-grant publication
B2	Utility patent, with pre-grant publication
C	Reexamination certificate	C1, C2, C3, etc.
E	Reissue patent
F	Supplemental examination certificate	F1, F2, F3, etc.
H	Statutory invention registration (SIR)	Discontinued in 2013
J	Post grant review certificate	J1, J2, J3, etc.
K	Inter partes review certificate	K1, K2, K3, etc.
O	Derivation certificate	O1, O2, O3, etc.
P1	Plant patent application, first publication
P2	Plant patent, no pre-grant publication
P3	Plant patent, with pre-grant publication
P4	Plant patent application, second or subsequent publication
P9	Plant patent application, correction
S	Design patent

Table 2. Obsolete U.S. Patent Document Kind Codes (codes used prior to January 2, 2001)

Code	Document Type	Notes
A	Patent	Replaced by B1 or B2
P	Plant patent	Replaced by P2 or P3
B1, B2, B3	Reaxmination certificate	Replaced by C1, C2, C3, etc.

Sources

Manual of Patent Examining Procedure, 9th ed., March 2014

WIPO Standard ST.16:  Identification of Different Kinds of Patent Documents (May 1997)