S&P 500 Index surged on Thursday, lifted by earnings reports and fewer than expected unemployment claims. S&P benchmark index gained 0.49% or 6.46 points and finished at 1,314.5 with eight out of ten sectors reporting gains. F5 Networks Inc. rallied 11%, after the manufacturer of Internet networking equipment reported an increase in earnings and a optimistic profit outlook. Sears Holding Corp. rocketed 10% on speculation the firm may be taken private by majority owner E. Lampert. Ebay Inc. climbed 3.9% after beating Wall Street earning predictions and giving positive outlook for 2012.