Precision Castparts - The supplier of metal components fell after reporting quarterly earnings below expectations.
Qualcomm - The chip manufacturer declined after projecting quarterly profit that could miss estimates.
SodaStream International - Shares were halted after Bloomberg cited people familiar with the matter in reporting the Israeli maker of home-soda machines company was in talks with an investment firm about going private.
Tractor Supply Company - The operator of farm and ranch stores gained after Wedbush reiterated its outperform rating.
TripAdvisor - The provider of travel reviews fell after posting second-quarter earnings short of estimates.
Under Armour - The maker of sports apparel rose after hiking its full-year sales outlook.
Read MoreUnder Armour gains from strong demand for sportswear, shoes
Zillow - The real estate site gained after Bloomberg cited people with knowledge of the matter in reporting the company was trying to purchase competitor Trulia.
See CNBC's Market Insider Blog
—By CNBC's Kate Gibson.
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