JC Penney, Netflix, Micromet are big movers J.C. Penney Co. Inc., up $6.44 at $40.72 The department store chain, which is trying to reinvent itself, posted a 2012 profit outlook that was above what analysts expected. Briggs & Stratton Corp., down $1.50 at $15.70 The engine maker said it will close a plant in Tennessee and shift the work to Georgia, eliminating about 690 jobs in the U.S. United Rentals Inc., up $3.10 at $37.87 The company, which rents heavy equipment such as forklifts, posted fourth-quarter earnings that handily beat Wall Street expectations. Caterpillar Inc., up $2.26 at $111.31 The maker of construction and mining equipment said that its fourth-quarter profit jumped 60 percent, on demand for new equipment. Netflix Inc., up $20.97 at $116.01 The video subscription service said that it added 600,000 subscribers, almost as many customers as it lost after a price increase. Arctic Cat Inc., up $4.77 at $28.58 Higher sales of its snowmobiles and all-terrain vehicles helped the company nearly double quarterly earnings and beat expectations. Micromet Inc., up $2.66 at $10.94 Amgen, the world's largest biotech company, said it is buying the developer of cancer therapies for $1.16 billion in cash. Republic Airways Holdings Inc., up 80 cents at $5.33 The airline raised its outlook for certain key metrics thanks to the strong performance of its Frontier Airlines service.