You have probably heard of some major urban legends -- and with any luck, you don't believe them. For example, if you've received an email warning you about a new danger for travelers -- that you may be drugged at a hotel bar and then wake up in a bathtub full of ice, with lower back pain and two missing kidneys -- know that it's a myth.

There are lots of circulating urban legends that involve companies we know and in which we're often invested. It's good to know about these, because if they become widespread and widely believed, they can hurt the companies. One top website to consult whenever you suspect you might be dealing with an urban legend is Here are some top urban legends, per Snopes, that deal with public companies:

  • Myth: Bill Gates, Microsoft (NASDAQ:MSFT), and an online access provider are giving away cash and merchandise to those who forward an email message, versions of which have apparently been around since 1997. Rest assured that these companies are not so stupid that they'll pay us each tens of thousands of dollars to test their "email tracking system."
  • Myth: Target (NYSE:TGT) stores do not support veterans. This myth has several versions, all false. It's not true that Target does not contribute to veterans' causes, or that it is French-owned, for example. (Though I scratch my head at vilification of the French in the name of patriotism. After all, the French were pivotal in helping America achieve its own independence, even though France was a monarchy at the time.)
  • Myth: A new Pepsi can design omits the words "under God" from the Pledge of Allegiance. This is actually very slightly based in truth, though about a different company. Back in 2001, Dr. Pepper, a brand owned by Cadbury-Schweppes (NYSE:CSG), not PepsiCo (NYSE:PEP), evoked the Pledge of Allegiance on a can by using three words from it -- "One nation. indivisible." It didn't include the entire pledge except for "under God." (By the way, Philip Durell discussed Cadbury-Schweppes earlier this year in an article titled "Dirt Cheap Dream Stocks.")
  • Myth: Procter & Gamble's (NYSE:PG) Swiffer WetJet is dangerous to pets. It's not almost the same as anti-freeze, and it shouldn't shut down your dog's liver system.
  • Myth: Gang initiates are being required to kill a woman and small child in a Wal-Mart (NYSE:WMT). Not true. Sheesh.
  • True! Sears (NASDAQ:SHLD) pays the difference in salaries and maintains benefits for their called-up military reservist employees. Unlike most others, this urban legend is actually true. explained: "Sears is indeed one of the employers who take additional steps to show support for employees involved in serving their country (either in the Reserves or the National Guard) by guaranteeing the continuance of their civilian pay (for up to 60 months) and allowing continued participation in life insurance, medical, and dental programs."

So get your facts straight before you go boycotting any company needlessly, and as an investor be aware of any false stories circulating about companies you own -- they have the power to do real damage.

For your further reading pleasure, here are some articles of possible interest:

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Longtime Fool contributor Selena Maranjian owns shares of Wal-Mart, PepsiCo, and Microsoft. The Fool has an ironclad disclosure policy.