Shares of Citrix Systems (CTXS) topped the S&P 500 on Wednesday with an 8 percent gain, making it TheStreet's Move of the Day. Share rose after the company announced a cooperation agreement with activist investment firm Elliott Management on Tuesday, which already has a 7.5 percent stake in the company. Jesse Cohn, head of U.S. equity activism at Elliott, will be joining the board of Citrix, replacing Asiff Hirji. Plus, the software company's CEO Mark Templeton announced his retirement, after a 21-year tenure. Shares were also boosted after beating Wall Street's top and bottom line estimates for second quarter results, released Tuesday. Earnings per share came in at $1.00, ahead of the $0.82 analysts were looking for. Revenue of $796.76 million eclipsed analysts’ estimates of $790.37 million and rose 2 percent year-over-year. The stock trades near $75.36. Shares have risen 18.2 percent since the start of the year. TheStreet's Scott Gamm reports from New York.