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: Amarin (Nasdaq: AMRN) shares jumped 10% in intraday trading today on very high volume.

So what: The biopharmaceutical company has already seen 5 million shares trade hands with two hours left in the trading day versus a daily average of 2 million shares. There was no new news from the company today, so it looks like the short squeeze is on.

Now what: There is some crazy price action today, and the stock, which didn't jump at the open, has seen two major spikes during the day. Last week, Foolish colleague Rich Duprey pointed out the spike in short interest in November and a spike like that often times leads to a short squeeze. But beware buying on a short squeeze as a stock can fall just as fast in coming days.

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

Fool contributor Travis Hoium does not have a position in any company mentioned. You can follow Travis on Twitter at @FlushDrawFool, check out his personal stock holdings or follow his CAPS picks at TMFFlushDraw.

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