LinkedIn, the social network for professionals, on Thursday slashed its full-year forecast and reported its slowest quarterly revenue growth since it went public four years ago. The weak results followed Twitte's on Tuesday. Twitter's stock fell by as much as 24 percent, slicing about $6 billion off its market value. LinkedIn also lost more than $6 billion of market value after the company announced its full-year forecast.

LinkedIn cited slower revenue growth in its hiring business and a delay in recognizing revenue from the acquisition of lynda.com for its weaker results.