; (B) by redesignating subsections (c), (d), and (e) as subsections (d), (e), and (f), respectively; (C) by inserting after subsection (b) the following: (c) Single forum (1) In general If an inter partes 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 on any ground described in section 311(b). (2) Considerations In determining whether to institute a proceeding under this chapter, subject to the provisions of subsections (a)(1) and (g), the Director may not reject a petition requesting an inter partes 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 applicable 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 ).