37 CFR §42.102

1. (a)A petition for inter partes review of a patent must be filed after the later of the following dates, where applicable:
   1. (1)If the patent is a patent described in section 3(n)(1) of the Leahy-Smith America Invents Act, the date that is nine months after the date of the grant of the patent;
   2. (2)If the patent is a patent that is not described in section 3(n)(1) of the Leahy-Smith American Invents Act, the date of the grant of the patent; or
   3. (3)If a post-grant review is instituted as set forth in subpart C of this part, the date of the termination of such post-grant review.
2. (b)[Reserved]