Stocks that moved substantially or traded heavily Thursday on the New York Stock Exchange and Nasdaq Stock Market:
Thermo Fisher Scientific Inc., up $2.64 at $65.38
The scientific instrument maker will buy Swedish company Phadia, which makes blood test systems, for $3.5 billion.
Big Lots Inc., down $3.97 at $33.77
The discount chain decided not to sell itself because bids were too low, according to The Wall Street Journal.
Macy's Inc., up 30 cents at $29.50
Standard & Poor's lifted the department store chain's credit rating as its sales improve and it pays down debt.
GameStop Corp., up 64 cents at $27.32
The video game retailer, which also runs the EB Games brand, provided a disappointing forecast for the current quarter.
Advance Auto Parts Inc., down $7.17 at $63.49
The automotive aftermarket parts retailer reported first-quarter results that missed Wall Street estimates.
Pure Bioscience, up 22 cents at $1.25
The sanitizer developer said that its antibacterial formula appears effective against a bacterial film linked to infections.
PetSmart Inc., up $3.22 at $45.71
The pet products store chain raised its full-year earnings guidance after reporting first-quarter profit climbed 28 percent.
Dollar Tree Inc., up $1.78 at $63.11
The discount retailer said first-quarter net income rose on strong sales, and it raised its sales and profit forecast for the year.