Twitter and Wal-Mart fall; ICU Medical and Lam Research jump

NEW YORK (AP) - Stocks that moved substantially or traded heavily on Thursday:

Twitter Inc., down $5 to $19.87

Investors felt it is less likely the social network will be bought by another company.

Zumiez Inc., up $2.88 to $21.15

The teen retailer said an important sales measure improved in September, a surprise to analysts.

ICU Medical Inc., up $18.72 to $144.68

The company agreed to buy an infusion pump business from Pfizer for $1 billion in cash and stock.

Yum Brands Inc., down $1.18 to $87.44

The parent of Taco Bell and other chains reported disappointing quarterly results as sales in China slumped.

Mylan Inc., down $1.19 to $36.84

The administrator of Medicare said it appeared Mylan had overcharged the government for its EpiPen allergy shot.

Wal-Mart Stores Inc., down $2.31 to $69.36

Investors weren't enthusiastic about the retail giant's profit projections for the next few years.

Lam Research Corp., up $4.02 to $100.19

The semiconductor equipment maker called off a merger with rival KLA-Tencor after facing opposition from antitrust regulators.

Buckle Inc., down $2.41 to $21.24

The teen clothing retailer reported an even larger drop in sales than analysts had expected.