Nadex Adds Strikes on a Discretionary Basis in its Daily Metals, US Indices, and Germany 30 Event contracts for Trade Date September 27, 2011, in its Daily Silver Event contracts for Trade Date September 28, 2011 and Amends the Strike Interval Width in

Pursuant to Section 5c(c)(1) of the Commodity Exchange Act, Commission Regulation §40.6(c), and by the authority granted by Nadex Rules 12, Nadex has added additional strike levels on a discretionary basis in its Daily US 500, US Tech 100, US SmallCap 2000, Wall St 30, Germany 30, Silver and Gold Event contracts for trade date September 27, 2011, and in its Daily Silver Event contracts for trade date September 28, 2011 only, due to volatility in the underlying markets on those days. Additionally, Nadex amends the strike interval width in its Daily, Weekly and Intraday Silver Event contracts effective October 3, 2011.