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: Berkshire Hathaway's bid to buy Lubrizol (NYSE: LZ) set off a chain reaction among specialty chemical makers, and helped lift NewMarket (NYSE: NEU) in particular 12% this morning -- on absolutely no other news of note.

So what: Exactly. "So what?" Just because Warren Buffett believes Lubrizol is worth 12.3 times earnings doesn't mean NewMarket is worth that much. But it's probably no coincidence that this is almost precisely the price investors are now paying for NewMarket in the wake of Lubrizol's news.

Now what: Time for a logic check, folks. If 12.3 times earnings is the "right" price for chemicals concerns, this would imply that DuPont (NYSE: DD) is nearly 33% too expensive, and that Dow Chemical (NYSE: DOW) costs nearly twice as much as it should. But don't hold your breath waiting for a 50% stock drop at Dow, just because Buffett is buying someone else entirely. As for NewMarket itself, it pays a similar dividend yield to Lubrizol's, is growing no faster than its larger rival, and generates net profit margins only 73% as rich as Lubrizol's. Maybe some investors think these are good reasons to bid the shares up 12% today. I disagree.

Want to keep closer track of NewMarket, and see if it holds onto its gains? Add it to your watchlist.

Fool contributor Rich Smith does not have any position in any company named above. The Motley Fool has a disclosure policy.

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