The session may feature some fireworks, especially later in the day, as Standard & Poor's "full-float" conversion occurs at the end of the session amid "quadruple witching" during the day.
By going to full-float, certain stocks on S&P indexes, including the S&P 500, will see their weightings change, meaning investors who try to emulate the index's performance could, on Friday, find themselves scrambling to buy and sell the shares that are affected so that their portfolios can stay in sync with the weightings on the index.