On Monday, a group of companies that included Amazon, Facebook, Apple, Twitter, Microsoft, and Netflix filed an amicus brief in a California court arguing against the U.S.’s temporary ban on H-1B and other visas. Trump announced the visa suspensions on June 22 and said they would last until at least the end of 2020.

“The suspension of these vital nonimmigrant visa programs will stifle innovation, hinder growth, and ultimately harm U.S. workers, businesses, and the economy more broadly in irreparable ways,” the Monday brief said.

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The move throws the weight of the U.S. tech industry behind a lawsuit filed in July by leading business groups, such as the U.S. Chamber of Commerce, against the U.S. government over Trump’s order.

U.S. tech firms got involved in the lawsuit because they depend heavily on the H-1B visa program that allows U.S. companies to hire foreign talent. H-1B visas are granted to foreign workers with “specialized knowledge” and are primarily used by tech companies to hire individuals from India. In 2019, roughly 65% of H-1B visa holders in the U.S. worked in computer-related occupations, and Amazon, Google, and Facebook were among the companies with the most employees on H-1B visas.

In June, Trump said that the visa ban was necessary owing to the U.S.’s “extraordinary” economic contraction amid the pandemic and argued that issuing visas to foreign workers posed “an unusual threat” to American workers.

Immediately following the June order, top tech executives expressed opposition to the move.

“Like Apple, this nation of immigrants has always found strength in our diversity, and hope in the enduring promise of the American dream,” Apple CEO Tim Cook said on Twitter in June. “There is no new prosperity without both. Deeply disappointed by this proclamation.”

Monday’s brief called the ban “fundamentally un-American” and said it would do “irreparable damage” to the country’s economy.

Trump’s ban “prevents U.S. companies from attracting the world’s best and brightest, and deprives those innovative, highly skilled individuals of opportunities to further America’s short-term recovery and long-term economic growth,” the brief said.

Google, Spotify, and Bloomberg together filed a separate request to support the lawsuit against the temporary visa ban.

Big Tech’s defense of the H-1B visa comes as the Trump administration continues to crack down on the program, even beyond the June ban. Last week, Trump signed an executive order to bar H-1B visa holders from replacing American workers on federal contracts.

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