On February 9, 2015 north American Derivatives Exchange, Inc. (NADEX) published a notice concerning its bitcoin contracts. The company detailed a halt in trading of its daily and weekly bitcoin binary contracts, based on the so called unavailability of the price index that underlies the contracts – the Tera Bitcoin Price Index.
The release went on to detail that NADEX would not be issuing any new daily bitcoin contracts until further notice (no specifics given), but that it would resume trading in the weekly contracts as soon as the Tera price feed was back up and running.
http://www.newsbtc.com/2016/02/10/nadex-halts-bitcoin-options-contracts-cites-price-feed-unavaliability/
