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 industrial engineering specialist EnPro Industries (NYSE: NPO) blinded Mr. Market with science today, jumping as much as 12.1% according to some market trackers but only 8% according to others. Either way, trading volumes were high and the jump still impressive.

So what: EnPro insiders have been buying the stock over the summer, and now we know why: The third-quarter report trounced analyst estimates on both the top and bottom lines. The fourth-quarter outlook also blasted Wall Street's expectations out of the water.

Now what: Whichever of the reported jump levels you look at, EnPro deserved every bit of it and then some. The company's operating margins are much stronger than those of rivals Federal-Mogul (Nasdaq: FDML) and Meritor (NYSE: MTOR), and fully in class with industry giant Caterpillar (NYSE: CAT). Shares trade at a premium to the rest of the industry, but sometimes you get exactly what you pay for: The bottom-line growth in spite of the very mature industry is out of control.

Interested in more info about EnPro Industries? Add it to My Watchlist.