On Friday January 28, 2011, AGA filed a petition for judicial review of EPA’s greenhouse gas reporting rule for natural gas systems (40 C.F.R. Part 98, Subpart W) in the U.S. Court of Appeals for the D.C. Circuit. AGA believes it should be possible to reach a settlement and have EPA agree to issue a rule amendment to resolve the relevant issues, but in case that is not possible, by filing this petition, AGA preserves its right to challenge the rule in court. AGA’s main issues with the rule are as follows: (1) the terms “custody transfer city gate station” and “non-custody city gate station” are subject to conflicting interpretations that make it difficult to comply with the rule; and (2) the formula for calculating emissions from city gate stations contains serious errors that would potentially inflate emissions by a significant amount. It was not possible to comment on these issues during the comment period on the proposed rule, because the terms and formula did not appear in the proposed rule. They appeared for the first time in the final rule published in November.