A group of 97 tech companies signed on to a friend-of-the-court brief filed Sunday that strongly opposes President Trump’s move to block immigration and travel from seven Muslim-majority nations.

Companies backing the brief include Apple, Google, Facebook, Netflix, Microsoft, Twitter, Snap, Spotify and Uber.

Trump’s Muslim ban “represents a significant departure from the principles of fairness and predictability that have governed the immigration system of the United States for more than 50 years — and the Order inflicts significant harm on American business, innovation and growth as a result,” the companies said in their brief, filed Feb. 5 with the 9th Circuit Court of Appeals.

The filing is the most unified stand yet by Silicon Valley against the Trump administration’s action, which is purportedly aimed at restricting the ability of terrorists to enter the U.S. (Amazon was not a signatory to the brief although the the company has supported legal action in Washington State against the Trump order.)

The amicus brief comes after Trump’s anti-Muslim travel and immigration order was struck down Friday by a federal judge in Washington, and the appeals court denied the White House’s motion for an emergency injunction reinstating the ban earlier Sunday.

An open letter to Trump from several big technology firms voicing their concerns about and opposition to the ban was reportedly in the works last week. Earlier, several tech CEOs publicly blasted the Jan. 27 executive order — including Netflix chief Reed Hastings, who labeled it “un-American” — and last week employees of Google and Comcast staged protests against the ban.

In their amicus filing Sunday, the 97 technology firms said Trump’s Executive Order “makes it more difficult and expensive for U.S. companies to recruit, hire, and retain some of the world’s best employees. It disrupts ongoing business operations. And it threatens companies’ ability to attract talent, business, and investment to the United States.”