While company earnings are supposed to drive the market higher or lower, that only seems to be the case on those few days of the year when the company officially reports earnings or announces possible future results. Most of the time, a stock moves higher or lower because of negative news, rumors, mergers, or a competitor's positive or negative results. Today, the majority of the Dow Jones Industrial Average's (DJINDICES:^DJI) stocks are moving because of the latter, not actual company earnings. The index itself managed to move slightly higher, gaining just 17 points, or 0.13% and now rests at 13,488.

Of the Dow's 30 components, 15 of them ended the trading day in the red. This afternoon, I explained why three of the biggest Dow losers were Boeing (NYSE:BA), Bank of America (NYSE:BAC), and Hewlett-Packard (NYSE:HPQ). To read about what negative news helped push these companies lower, click here. Or stick around to learn about the outside forces affecting the stock prices of UnitedHealth (NYSE:UNH), Verizon (NYSE:VZ), and AT&T (NYSE:T).

So what happened?
Shares of UnitedHealth lost 0.55% today as investors fear this year's flu season may hurt the company's earnings. It's been reported that incidents of the flu in the final quarter of 2012 hit their highest level since 2009  and just yesterday reports spread that the U.S. faces a shortage of the flu vaccine. One analyst from Susquehanna Financial Group says that long-term investors should not worry about this flu season or any other, because it is unlikely to have any real effect on earnings over the long run.

Both of the Dow's telecommunications stocks fell today, possibly for the same reason: rumors of large purchases in their future. Shares of Verizon ended the day down 0.67% while AT&T's lost 0.29% of their value. Verizon CEO Lowell McAdam recently told The Wall Street Journal that his company would "love to own all of that asset," referring to Verizon, which only owns 55% of itself while Vodafone (NASDAQ:VOD) owns the other 45%. He went on to say, "I think [a deal] is feasible." One analyst puts a price tag of $107 billion for Vodafone's share of the company.  

As for AT&T, as the battle over spectrum heated up this week, talk that the company may still be interested in Dish Network's (NASDAQ:DISH) spectrum hit front and center when Dish offered to purchase more spectrum with its buyout offer of Clearwire on Tuesday. It is now believed that if AT&T wants any of the asset from Dish, it would have to purchase the whole company, not just cherry-pick the good parts. At Dish's current market capitalization of $16.35 billion, a buyout offer would be rather pricey for AT&T right now.  

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Matt Thalman owns shares of Bank of America. Follow Matt on Twitter @mthalman5513. The Motley Fool recommends UnitedHealth Group and Vodafone Group Plc (ADR). The Motley Fool owns shares of Bank of America. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.