The firm said it changed its rating for the technology company, which focuses on automating the buying and selling of advertising, based on a valuation call and the company's 2014 first quarter revenue results.
After the close on Tuesday Rubicon reported revenue for the most recent quarter increased 39% to $23 million, from $16.6 million for the 2013 first quarter.
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Separately, TheStreet Ratings team rates FACEBOOK INC as a Hold with a ratings score of C. TheStreet Ratings Team has this to say about their recommendation:
"We rate FACEBOOK INC (FB) a HOLD. The primary factors that have impacted our rating are mixed some indicating strength, some showing weaknesses, with little evidence to justify the expectation of either a positive or negative performance for this stock relative to most other stocks. The company's strengths can be seen in multiple areas, such as its robust revenue growth, largely solid financial position with reasonable debt levels by most measures and impressive record of earnings per share growth. However, as a counter to these strengths, we find that the stock itself is trading at a premium valuation."