; or (B) charged with infringement under the patent. . (d) Limitation on reviews Section 314(a) of title 35, United States Code, is amended to read as follows: (a) Threshold (1) Likelihood of prevailing Subject to paragraph (2), the Director may not authorize an inter partes review to be instituted unless the Director determines that the information presented in the petition filed under section 311 and any response filed under section 313 show that there is a reasonable likelihood that the petitioner would prevail with respect to at least one of the claims challenged in the petition. (2) Previous institution The Director may not authorize an inter partes review to be instituted on a claim challenged in a petition if the Director has previously instituted an inter partes review or post-grant review with respect to that claim. . (e) Reviewability of institution decisions Section 314 of title 35, United States Code, is amended by striking subsection (d) and inserting the following: (d) No appeal (1) Nonappealable determinations (A) Threshold determination A determination by the Director on the reasonable likelihood that the petitioner will prevail under subsection (a)(1) shall be final and nonappealable. (B) Denials of institution A determination by the Director not to institute an inter partes review under this section shall be final and nonappealable. (2) Appealable determinations Any aspect of a determination by the Director to institute an inter partes review under this section, other than a determination described in paragraph (1)(A), may be reviewed during an appeal of a final written decision issued under section 318(a). . (f) Eliminating repetitive proceedings Section 315(e) of title 35, United States Code, is amended to read as follows: (e) Estoppel (1) Proceedings before the office A person petitioning for an inter partes review of a claim in a patent under this chapter, or the real party in interest or privy of the petitioner, may not petition for a subsequent inter partes review before the Office with