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 supplemental insurance giant Aflac (NYSE: AFL) fell as much as 10.9% today on very heavy trading.

So what: Not only does Aflac do about 75% of its business in Japan, which would be bad enough, but a longtime and very successful promotion partnership with comedian Gilbert Gottfried came to an abrupt end today.

Now what: Gottfried made some very tasteless tsunami jokes in the very public forum of Twitter, leaving Aflac no choice but to cook his goose. That adds to an already difficult situation, as the company we know as a workplace policy provider is the largest insurer of any kind in Japan. The damage control for Gottfried's antics is done; now it's up to Aflac to revamp that ducky ad campaign while dealing with a flood of legit claims from disaster victims. This will hurt for a while.

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Fool contributor Anders Bylund holds no position in any of the companies discussed here. Aflac is a Motley Fool Stock Advisor selection. The Fool owns shares of Aflac. 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 is investors writing for investors.