On January 23, the CFTC extended the comment period for the supplemental proposal for Regulation Automated Trading (Regulation AT) from January 24 to May 1. Acting CFTC Chairman Chris Giancarlo recently announced his intention to “allow more time for public comments on the proposal” in light of “the complexity of the supplemental notice and the well-reasoned requests from interested parties.”  Initially proposed in November 2015, the CFTC released a revised version of the rule in November 2016 in response to concerns expressed by trading firms over, among other things, the requirement that they make their source code available to the agency without a subpoena. All comments will be posted on the CFTC’s website.