Marvell ($MRVL) stock jumps 9% premarket on news it will join the S&P 500. Read why index inclusion is sparking a massive rally.

June 5 : Marvell Technology is set to join the benchmark S&P 500 index, S&P Dow Jones Indices said on Friday, sending the chipmaker's shares up 6 per cent in extended trading.The…

The move highlights the growing importance of the technology sector to the stock market.