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What: Shares of printer maker Lexmark International (NYSE: LXK) cratered this morning, landing nearly 21% below last night's closing price

So What: Last night's third-quarter report wasn't terrible; Lexmark beat earnings expectations and guided up for the next quarter. However, longtime CEO Paul Curlander also announced his retirement, effective in the spring of 2011.

Now What: Paul Rooke, Curlander's replacement, has long been heir apparent to Lexmark's throne, and has been with the company since it was spun off from IBM (NYSE: IBM) in 1991. While the actual passing of the baton may not have been a surprise, the timing of the event certainly was. Lexmark's business is doing quite well, despite the much-publicized lack of consumer interest in computing products and strong competition from Hewlett-Packard (NYSE: HPQ), and Curlander is retiring at a fresh-faced age of 57.

Interested in more info on Lexmark? Add it to your watchlist.

Fool contributor Anders Bylund holds no position in any of the companies discussed here. The Fool owns shares of International Business Machines. 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.