; (2) by inserting after subsection (b) the following: (c) Single forum (1) In general If a post-grant review is instituted challenging the validity of a patent, the petitioner, a real party in interest, or a privy of the petitioner may not file or maintain, in a civil action arising in whole or in part under section 1338 of title 28, or in a proceeding before the International Trade Commission under section 337 of the Tariff Act of 1930 ( 19 U.S.C. 1337 ), a claim, a counterclaim, or an affirmative defense challenging the validity of any claim of the patent. (2) Considerations In determining whether to institute a proceeding under this chapter, subject to the provisions of subsections (a)(1) and (h), the Director may not reject a petition requesting a post-grant review on the basis of the petitioner, a real party in interest, or a privy of the petitioner filing or maintaining a claim, a counterclaim, or an affirmative defense challenging the validity of the patent in any civil action arising in whole or in part under section 1338 of title 28, or in a proceeding before the International Trade Commission under section 337 of the Tariff Act of 1930 ( 19 U.S.C. 1337 ). ; (3) by amending subsection (e), as so redesignated, to read as follows: (e) Multiple proceedings (1) In general Notwithstanding sections 135(a), 251, and 252, and chapter 30, after a petition to institute a post-grant review is filed, if another proceeding or matter involving the patent is before the Office— (A) the parties shall notify the Director of that other proceeding or matter— (i) not later than 30 days after the date of entry of the notice of filing date accorded to the petition; or (ii) if the other proceeding or matter is filed after the date on which the petition to institute an inter partes review is filed, not later than 30 days after the date on which the other proceeding or matter is filed