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For a good chunk of the trading day today, investors weren't able to trade stocks listed on the Nasdaq OMX Group's (NDAQ -0.03%) namesake Nasdaq exchange. No buying. No selling. No shorting. You couldn't even throw on some last-minute hedges using options. The exchange was simply shut down, and investors who owned a Nasdaq-listed stock -- like Apple, Google, or, um, Nasdaq OMX -- had to be content continuing to own it until the exchange opened back up.

While there are undoubtedly many folks intensely frustrated with this failure -- which is being chalked up to a computer glitch -- I can bet there's at least one investor that hasn't even broken a sweat. That investor is none other than Berkshire Hathaway CEO Warren Buffett.

Here's what Buffett has famously said about stock trading and the existence (or not) of stock exchanges:

I never attempt to make money on the stock market. I buy on the assumption that they could close the market the next day and not reopen it for five years.

In this day and age, there's little reason to think that an investor would be put in a position where they wouldn't be able to unload a stock for five years. But there is good reason to think exchange glitches like this aren't an unheard-of anomaly. A trading glitch at KCG Holdings (NYSE: KCG) -- formerly Knight Capital Group -- disrupted trading for hours on end and nearly wiped the company out. When Facebook (META -1.12%) held its infamous IPO, computer issues at the Nasdaq caused massive problems at the open of trading. Of course, there was also the Flash Crash. And if you Google "flash crash," you can spend days reading about a variety of other smaller glitches and flukes.

You don't have to look far to find commentators who are pulling their hair out over this. And some businesses do have reason to be concerned -- if a brokerage can't trade Nasdaq-listed stocks for multiple hours during a day, they don't make money. Yet I can't seem to get my blood pressure up over episodes like this.

The bottom line is that Buffett has it exactly right. When investors buy a stock, they're not buying a piece of paper, they're buying an ownership stake in an operating business. The Motley Fool has espoused this for more than 20 years now. In fact, if you hear a reference to the idea of "Foolish investing," this concept of owning business stakes as opposed to trading slips is absolutely central to that.

The trading snafu with Facebook's IPO caused a lot of confusion. But what it didn't do was impact the business. The ability to swap claim checks on the business was disrupted, but the massive, growing social networking business that connects individuals all over the globe wasn't. Likewise today, even though traders may not have been able to sling Google shares for a few hours, that had nothing to do with the business's operations or ability to continue taking over... well, most aspects of our online lives.

So, go ahead and take note of what went on today on the Nasdaq exchange. But unless you're a Nasdaq shareholder -- since this is a business issue for Nasdaq -- feel free to flip back up to the quote from Warren Buffett and go right on being a content business owner.