US stocks open lower as geopolitical worries weigh

Altera Corp Amazon.com Assurant Baidu.com SP ADR Biogen Idec Boeing Co Bristol-Myers Squibb Caterpillar Cheesecake Fact Chubb Corp Comcast Corp Credit Suisse Group Credit Suisse Group ADR Dow Chemical Dr. Pepper Snapple Group DuPont USA Dunkin' Brands Group EMC Corp Electronic Arts Eli Lilly F5 Networks Facebook Flextronics Intl Ltd Freeport-McMoRan General Motors Genl Dynamics Gilead Sciences Grubhub Ord Shs Halliburton Co Harley-Davidson Imax Corp International Business Machines Jetblue Airways Cp Juniper Networks KLA-Tencor Corp Kimberly-Clark Lockheed Martin Mettler-Toledo International Microsoft Norfolk Southern Owens Corning Inc PepsiCo Praxair Qualcomm, Inc. Reynolds American Roche Holding AG Basel American Depositary Shares Roche Holding Ltd Sentinelone Inc Cl A Starbucks Corp T.Rowe Price Group TripAdvisor Under Armour Union Pacific United Technologies Verizon Communications Vmware Inc Wyndham Worldwide Xerox Corp Xilinx