The researchers said Indian immigrants founded more companies than those from the next four countries -- Britain, China, Taiwan and Japan -- combined.

Wed Aug 22, 12:53 PM ET

The huge backlog in US immigration visas is leading to a "reverse brain-drain" that will force skilled workers to return to their home country, a report released Wednesday concludes.

The study by the Ewing Marion Kauffman Foundation found that more than one million potential immigrants, including scientists, engineers, doctors and researchers, are competing for 120,000 permanent US resident visas each year.

The report said some applicants must wait several years, in part because the number of employment visas issued to immigrants from any single country is fewer than 10,000 per year.

"The United States benefits from having foreign-born innovators create their ideas in this country," said Vivek Wadhwa, a Harvard Law School fellow and co-author of the report.

"Their departures would be detrimental to US economic well-being."

The study by researchers at Duke, New York and Harvard universities is the third in a series of studies focusing on immigrants' contributions to the US economy.

In this study, "Intellectual Property, the Immigration Backlog, and a Reverse Brain-Drain," the researchers concluded that the number of skilled workers waiting for visas is significantly larger than the number that can be admitted to the United States.

"This imbalance creates the potential for a sizeable reverse brain-drain from the United States to the skilled workers' home countries," the foundation said.

The report said a majority of immigrant company founders, including many in the tech sector, came to the United States as students. Many ended up staying in the United States after graduation, with a number founding new companies.

It said 31 percent of the startups in tech centers had an immigrant key founder, including 52.4 percent in California's Silicon Valley.

The researchers said Indian immigrants founded more companies than those from the next four countries -- Britain, China, Taiwan and Japan -- combined.

They also concluded that foreign nationals living in the United States were inventors or co-inventors in 25.6 percent of international patent applications filed from the United States in 2006.

The total number of applicants and their family members waiting for permanent residence in the United States in 2006 was estimated at 1,055,084. Additionally, there were some 126,421 residents abroad waiting for visas, making a worldwide total of 1,181,505.

"Given that the US comparative advantage in the global economy is in creating knowledge and applying it to business, it behooves the country to consider how we might adjust policies to reduce the immigration backlog, encourage innovative foreign minds to remain in the country, and entice new innovators to come," said Robert Litan, vice president of research and policy at the Kauffman Foundation.

(http://news.yahoo.com/)