Thus if you place a limit order half way between the current Bid and Ask and
the underlying stock price moves towards your limit order, the Market Maker will do their job and «Provide a Market» at that price, thus executing your order.
Not exact matches
Even if an ETF has no buyers or sellers for several hours, the bid and ask
prices continue to
move in correlation with the market value of the ETF, which is derived from the
prices of individual
underlying stocks.
If the
underlying is a
stock for example, as the
price of the
stock moves up and down during the trading day, so will the Market Maker's fair value for the Option.
To directly answer your question, no, shorting the S&P futures won't
move the
underlying prices of the 500
stocks.
A liquidation thereby acts as a tether to reality for the
stock market, forcing either undervalued or overvalued share
prices to
move into line with actual
underlying value.
In the case of Assignment, the option holders end up exercising their right to buy the
underlying stock (in the case of a call) or sell the
underlying stock (in the case of a put) at the strike
price should it
move «in the money» prior to expiration.
The longer an option has until its expiration date, the more time the
underlying stock price has to
move, which makes the option more valuable.
Delta measures the rate at which the
price of an option is expected to change when the
underlying stock or index
moves one point.