As any technology executive in Silicon Valley could tell you, hiring engineers is one of their toughest tasks these days.

A report from startup Identified shows just how in demand engineers are. People with engineering degrees on Identified have Identified scores that are 1.2 times those of liberal arts majors with equivalent work experience, meaning they are more sought after for jobs. But even in non-technical fields, people with engineering degrees are more sought after than liberal arts majors with the same years of work experience.

This difference increases with more years of experience. At five years of experience, those with engineering degrees in technical fields had a score of 68, compared with a 60 for engineers in non-technical fields and 51 for liberal arts majors.

How are the scores created? Identified scores combine people's education, work experience and social network, as well as how often companies search for, view, contact or hire people with similar profiles. I recently wrote about Identified's launch and how the company analyzes people to score people on a number from 1 to 100.

A number of tech executives and venture investors have gotten behind the Startup Visa idea, which would enable immigrant founders who create jobs through their new companies to stay in the U.S. That proposal, introduced in March, has not gotten through a divided Congress.

What's behind the high demand for engineers? There's an increasing demand both from tech companies and non-tech companies for highly-skilled engineers to create, build and maintain high quality systems at various levels from manufacturing to product design. Software is one major area of growth where engineers are needed in many companies.

But growth in engineering grads has not kept pace, Identified's report shows. Many tech companies therefore hire engineers who have been educated overseas. The U.S. H1-B Visa program was designed to bring talented "speciality occupations" such as engineers into the U.S. However the number of H1-Bs issued peaked in 2001 with 161,000. That number dropped to 110,000 such visas in 2009.

Which tech companies most rely on foreign-educated engineers? Some of the biggest names in technology. Microsoft, Google, IBM, Accenture and Cisco, in descending order, have the most foreign educated engineers, according to data compiled on employment and education from people on Identified. Even companies like Facebook, which are relatively young, have a sizable number of engineers educated abroad. This list only takes into account people who are on Identified and have their employment and education information listed. (See the chart.) By percentage of total employees at the company, NVIDIA, Sun Microsystems, AMD, and Oracle have the most engineers. While the list may not be a big surprise to anyone who is in SIlicon Valley, it is eye-opening to see just how much top technology companies rely on engineers who hail from outside the U.S.

Identified is not making any political arguments, but there is a need for engineers one way or another. "Just looking at basic labor supply numbers, there's clearly a shortage of engineers," says Identified CEO Brendan Wallace. "There's clearly a voracious demand. It's reflected in the Identified scores."