In three of the five solar stocks we track, short interest rose during the two-week period to August 15. The biggest movement was a rise in short interest in one stock. Fundamentally, the move in solar stocks was toward higher levels of short interest.

First Solar Inc. (NASDAQ: FSLR) saw short interest rise by 7.8% to 10.33 million shares, which represents 14.1% of the company’s float, and days to cover is three. In the two-week short interest period to August 15, shares rose 9.5%, and they are up more than 23% year-to-date through Tuesday’s close at $71.02. The stock’s 52-week range is $35.59 to $74.84.

SunEdison Inc. (NYSE: SUNE) showed a decrease of 1.1% in short interest to 66.71 million shares. About 25.1% of the company’s stock is now short, and days to cover is five. In the latest two-week short interest period, shares rose 6.7%, but they are up more than 62% year-to-date. The stock closed at $22.62 Tuesday night in a 52-week range of $7.08 to $24.35.

Sunpower Corp. (NASDAQ: SPWR) saw a short interest decline of about 1.4% to 10.93 million shares, or 21.1% of the company’s total float. In the two-week short interest period, shares slipped about 2.5%, but they are up more than 17% year-to-date after closing at $37.86 on Tuesday. The stock’s 52-week range is $21.00 to $42.07. Days to cover is 4.4.

SolarCity Corp. (NASDAQ: SCTY) showed a rise of 6.7% in short interest to 12.06 million shares, or 22.3% of the company’s float. Days to cover is 2.4. In the two-week short interest period, shares rose less than 0.5%, though they are up about 18% year-to-date through Tuesday’s close. The stock’s 52-week range is $28.31 to $88.35, and shares closed at $70.48.

GT Advanced Technologies Inc. (NASDAQ: GTAT) saw short interest rise by 17.2% to 56.54 million shares, about 41.5% of the company’s total float. Days to cover is 6.3. In the two-week short interest period, shares rose more than 25%. They are up nearly 104% year-to-date through Tuesday, when the shares closed at $18.60. The stock’s 52-week range is $6.28 to $20.54.

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