Following today's gains, Twitter (TWTR +5.7%) is up 23% on the week, and 113% from its $26 IPO price.
The microblogging service continues to unleash a torrent of new ad products. After launching its Tailored Audiences ad retargeting solution last week and a new TV ad product shortly before that, Twitter has launched Broad Match, an ad product that allows a keyword purchase to cover similar words.
In addition, the company's MoPub mobile ad network unit has added support for in-stream ads similar to Twitter's Promoted Tweets and Facebook's sponsored news feed ads. The products aims to profit from a general boom in demand for native advertising formats.
Short-covering could be contributing to this week's gains. As of Nov. 29, 17.8M Twitter shares were shorted; the company sold only 70M through its IPO.