Earnings reports and corporate announcements were some of the catalysts behind the most actively traded stocks on Monday.
Beijing-based online gaming company Perfect World jumped 10% on Monday, adding to lofty gains in its debut last week.
Shares gained 30% on Thursday after pricing above their expected range in a pocket of strong demand. Pricing of the IPO of 11.8 million shares was revised to $16 from the previous pricing range of $12 to $14 a share.
Perfect World's IPO follows offerings from fellow Chinese online gaming firms such as Shanda Interactive Entertainment and The9 Limited, which both have gained more than 100% in stock value since going public.
Shares of Vivus jumped more than 6% after the company received U.S. Food and Drug Administration approval of its spray to treat menopause-related symptoms. Regulatory clearance triggered a $140 million milestone payment from partner KV Pharmaceutical.
Auto parts maker ArvinMeritor saw shares rise after the company reported stronger-than-expected quarterly revenue. The company reported earnings of 25 cents a share on revenue of $1.66 billion. Analysts were expecting a profit of 25 cents per share on revenue of $1.53 billion, according to Thomson Financial.
Bear Stearns analyst Peter Nesvold maintained an "outperform" rating on the stock. "While far from a 'good' quarter, all considered we expected a lot worse given the operating environment," he wrote in a client note.
Moving to the downside, shares of ValueClick plunged more than 20% after the online advertising firm reported second-quarter earnings below expectations and cut 2007 guidance. The Westlake Village, Calif.-based company said second-quarter earnings rose 22% from the year-ago quarter but results came in below Wall Street expectations.
Peter Kang is a markets writer at CNBC.com and can be reached at firstname.lastname@example.org.