Quite a few bears are shaking in their portfolios today, at least as far as Marvel Entertainment is concerned. The stock has rallied more than 20% so far today after reporting solid first-quarter earnings, placing short-sellers in a bit of a bind. Currently, more than 15.5% of the stock's float is sold short, and it would take a lengthy 12.7 days to buy back these bearish bets at MVL's average daily trading volume. However, there could be a break over the near term for those bears that are able to ride out the storm.

While MVL is up more than 20%, the shares are struggling with resistance in the 28 region. On an intraday basis, the stock has not strayed more than 35 cents above this level - one that rejected the equity in early May and June already this year. If these short sellers get wind that the stock may be held in check at the 28 region, it could lessen the impact of any further short covering by the weaker hands.