Intuitive Surgical Inc. (ISRG) shares soared on a mixed day in trading Thursday, following its report of a 137 percent rise in quarterly earnings, helped by higher product revenue and gains on sales, according to Reuters.

Based in Sunnyvale, Intuitive is robotic surgical systems maker. It saw the highest share-price increase, 8.33 percent, of any of the 50 Bay Area public companies tracked by The Examiner Thursday. Its gains were followed by those of SunPower Corp. (SPWR), up 7.99 percent at close of trading Thursday.

EBay Inc. (EBAY) was trading down 6.16 percent at the close of market Thursday, the largest decline in stock price that day among any of the Examiner-tracked firms.

Sun Microsystems Inc. (JAVA) was the most heavily traded company among that list Thursday, with some 88.96 million shares changing hands.

The day ended with the Dow down .03 percent, the Nasdaq up .24 percent and the S&P 500 down .08 percent.