I learn something new every day. I had no idea that so many US companies (including Alliacense) are unable to find professionals who are U.S. citizens or residents

Overview: H-1B Visa is a non-immigrant visa which allows U.S. employers to temporarily employ foreign professionals in specialty occupations for three years, extendable to six years, if U.S. citizens or residents are not available.

http://www.myvisajobs.com/H1B_Visa.aspx

H1B and Green Card Yearly Acceptance/Denial Stats for ALLIACENSE LIMITED

http://www.visasquare.com/visa-greencard/report/alliacense-limited-189647.html

2012 H1B-Visa Sponsorship Reports By Companies

http://www.visasquare.com/top-h1b-visa-sponsors-2012/companies