Code

Description

CC

Certificate of Correction issued. This only indicates Certificates of Correction issued since 1986. The absence of this code does not guarantee that a particular patent has not been issued a certificate.

E1

 Expired four (4) years after the initial issue date.

E2

 Expired eight (8) years after the initial issue date.

E3

 Expired twelve (12) years after the initial issue date.

R1

 Reinstated after E1

R2

 Reinstated after E2

R3

 Reinstated after E3

B1

 Re-examined (before January 1, 2001)

B2

 Re-examined 2nd time (before January 1, 2001)

B3

 Re-examined 3rd time (before January 1, 2001)

C1

 Re-examined (after January 1, 2001)

C2

 Re-examined 2nd time (after January 1, 2001)

C3

 Re-examined 3rd time (after January 1, 2001)

W

 Withdrawn. Patent number was assigned and later withdrawn.

XT

 Term has been extended