Index options

Tented knows these indexes and picks the right exchange and trading class for each. A trading class is the option series IB lists under a ticker, such as SPXW for SPX weeklies.

Symbol	Index	Preferred trading class	Notes
SPX	S&P 500 Index	SPXW	Daily and weekly PM-settled expirations. Quotes from CBOE.
XSP	Mini S&P 500	XSPW	One-tenth of SPX size.
RUT	Russell 2000 Index	RUTW	Weekly chains preferred.
NDX	Nasdaq 100 Index	NDXP	Best chain through PHLX / NDXP.
DJX	Dow Jones Industrial Avg	DJX
VIX	CBOE Volatility Index	VIXW	Each expiration trades on its own month’s VIX future, not the index.

All of them are cash-settled index options worth 100 times the quoted price a point. In the chain the underlying price for SPX, XSP, RUT, NDX and DJX comes from the level their calls and puts imply by put-call parity, not the index print. See How Tented prices options and Chain price differs from the index print.

SPX AM and PM series

SPX lists two series: the PM-settled weeklies (class SPXW) and the AM-settled standard monthlies (class SPX). Tented picks one class for each expiration automatically. Where a date lists both, it uses the preferred class (SPXW). A date that only the SPX class lists is quoted and traded under SPX. You cannot choose between the two classes on one date.

VIX options

VIX options settle on the morning after their last trading day, at the opening (the Special Opening Quotation). Tented shows their time, expiry line and Expired state running to that Wednesday 09:30. The chain shows “forward” beside the price because each expiration is quoted against its own month’s VIX future. VIX futures themselves cannot be opened as an underlying.

SPXW, RUTW and VIX quotes between 09:25 and 09:30 ET are indicative; see Market data you need.