Exactly. If there is a large outstanding variance swap position in the market, dealer hedging could impact the behavior of SPX around the close. The interesting bit for a retail trader is the short-term trade opportunities that creates around the close - the actual change to daily volatility will be relatively small.
sle, this reminds me of open interest for options on single-names, kind of. Pin risk of some sort.
I've been utilizing wing-spreads a lot lately (ATMF put flies usually) on single-names and sometimes on index or ETF's.
But when I'm in the option chain, I do glance at the OI for different strikes, to gauge where other contracts are being traded at.
I also use volume by price, which IMO is an amazing "indicator", one of the few indicators I actually use when trading, it gives a good gauge on what prices have the most activity.
When you say "if theres a large outstanding var-swap position in the market" do you mean at an a specific strike level? Or multiple? I'm not even too sure if variance-swaps have strikes? I'm assuming they do though.
Could a retailer structure butterflies around this short-term trade opportunity around the close you speak of on the SPX?
Cheers

