quick q: ETF vs equity index futures, which one easy to short?

This is a QBank Q. I choose future, but the answer is ETF. Cant find it on notes at all!

it’s about uptick rule. p135.

" Re: quick q: ETF vs equity index futures, which one easy to short? new Posted by: deriv108 (IP Logged) Date: May 6, 2011 10:24PM it’s about uptick rule. p135. " Thanks!!! you remember all details, man!

hellscream Wrote: ------------------------------------------------------- > " > Re: quick q: ETF vs equity index futures, which > one easy to short? new > Posted by: deriv108 (IP Logged) > Date: May 6, 2011 10:24PM > > it’s about uptick rule. p135. > " > > Thanks!!! you remember all details, man! But uptick rule is no longer applicable. Please see the footnote on p220 vol 4 of CFAI text.

Why is uptick rule relevant for a stock index futures? If it was an individual stock itself, it would be OK, but how does it limit shorting a future?