Thirty-seven of the top 50 VC-funded firms have foreign workers in top-level production and management positions. (Tatan Syuflana/AP)

Evidently, immigrants play an enormous role.

Nearly half of the top 50 venture-backed firms in the country were founded at least in part by an immigrant, according to a new study by The National Foundation for American Policy. Expanded to include key management personnel, the portion of the top young companies headed by foreign individuals hikes up to 74 percent.

“It’s a gamble whether an entrepreneur should stay or leave right now, and that’s not how the immigration system should work,” Mark Heesen, president of the National Venture Capital Association, said in a statement. “What we need is legislation that helps these entrepreneurs from outside the United States.”

The study found that 46 percent (23 firms) of the top 50 venture-backed companies selected by Dow Jones’s Venturesource were started by at least one immigrant co-founder and that, on average, those companies created 150 jobs. Moreover, 37 of the top firms have foreign workers in top-level production and management positions.

VentureSource selected the top 50 VC-funded companies based on factors like company growth, successful chief executives and founders, and the amount of capital raised. Each is privately held and valued at less that $1 billion, and each has picked up venture capital funding within the last three years.

Among those with immigrant founders are Silicon Valley darlings like textbook-rental start-up Chegg, online dating service Zoosk, and online craft marketplace Etsy. The most common country of origin for immigrant founders from the top 50 firms was India, followed by Israel and Canada.

The results of the study provide additional ammunition to lobbyists, lawmakers and advocacy groups fighting for immigration reform, especially pertaining to those with advanced training and the wherewithal to launch their own firms. Most recently, House Judiciary Committee members announced plans to introduce a new bill in January that would improve green card access for highly educated immigrants, signaling that the debate will only heat up in the new year.

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