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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.

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