Online social-games maker Zynga climbed to its highest price since July on speculation that Yahoo! might consider buying the company.

The shares rose 10 percent to $3.91 at the close. The stock has advanced 67 percent this year, compared with a 9.4 percent gain for the Russell 1000 Index.

Yahoo! may consider buying Zynga as Chief Executive Officer Marissa Mayer seeks acquisitions to bolster the Web portal’s mobile and social capabilities, analyst Blake Harper wrote in a research report.