Video: The Shorts Are Back!

The shorts are back! Trading resurged following the expiration of the SEC's temporary ban against "naked" short selling of 19 financial stocks.

On Thursday, Jon Najarian, Fast Money regular and co-founder of, discusses the expiration -- and why shares of entities like Fannie Mae slipped.

More CNBC Investor Intelligence:

- 3 Stock Picks From Shorts' Clues

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