Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Diamond Foods (Nasdaq: DMND) have fallen 10% today after the company announced the SEC had opened a formal probe of its accounting practices.

So what: The SEC is investigating how the company accounted for payments last year, which may have been shifted to this year to boost earnings. As a result, Proctor & Gamble (NYSE: PG) said it wouldn't allow the $2.35 billion sale of Pringles to Diamond Foods go through until the investigation was complete.

Now what: To put salt in the wound, analysts at Jefferies downgraded the stock and now have a price target of $27, all the way from $94 in October. There's really nothing good to report here because you know it's bad news when the SEC starts snooping around your accounting offices. Shares are just too risky for this Fool right now, and I'll wait for more clarification around the investigation before considering buying.

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