Since its May 8 earnings report, Tesla Motors (NASDAQ:TSLA) has seen its shares soar. Great news had a lot to do with that, of course, but so did another factor: investors who had bet against the stock.

In this video, Fool contributor John Rosevear explains how investors who had sold Tesla's stock short actually contributed to its rise -- and whether the stock's impressive run is likely to continue for a while longer.

Fool contributor John Rosevear has no position in any stocks mentioned. Follow him on Twitter at @jrosevear. The Motley Fool recommends and owns shares of Tesla Motors. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.