The Chicago Board Options Exchange ("CBOE") proposes to amend Rule 24.7(a) to add additional facts that may be considered when determining whether to halt trading in volatility index options. Rule 24.7 is currently predicated on indexes being comprised of stocks and includes factors that may be considered by the CBOE when determining whether to halt trading based on the index components being stocks. The current filing amends Rule 24.7(a) to account for indexes comprised of options and allows the CBOE to consider the following factors when determining whether to halt trading:(1) whether the component options are not trading; (2) whether the "current index level" (as measured by the implied forward level based on volatility index (security) futures prices) is not available; or (3) whether the spot (cash) value for a volatility index is not available. SEC Release 34-70136.