Silicon Valley is stepping up its confrontation with the Trump administration.

Today, Uber, Twitter, Netflix and other prominent tech companies are planning to file legal brief opposing the administration's contentious travel ban on immigrants, according to people familiar with the matter.

The amicus brief is expected to be filed with the Ninth Circuit Court of Appeals, which is expected to rule within a few days on an appeal by the administration after a federal judge in Seattle issued late Friday a temporary restraining order putting the travel ban on hold. The brief comes at the end of a week of nationwide protests against the plan - as well as a flurry of activity in Silicon Valley, a region that sees immigration as central to its identity as an innovation hub.

Companies backing the filing also include Pinterest, Yelp, Square, Reddit, Kickstarter, Github, Glassdoor, Box, Mozilla, Dropbox, Twilio, Zynga, Medium, Pinterest, and Salesforce, according to the sources, who spoke on the condition of anonymity because the filing was still being finalized today.


Notably, it doesn't appear that Apple, Amazon, Microsoft, Google or Facebook are party to the brief. The sources cautioned the wording of the brief - and the participants - could still change before the filing is made today.

A draft of the filing says that the travel ban, which barred individuals from seven majority-Muslim countries from entering the U.S. for at least 90 days and suspended the U.S. refugee program, is discriminatory.

'The Order effects a sudden, seismic shift in the rules governing entry into the United States, and it departs dramatically from the principles that have governed our immigration law for decades," a draft obtained by The Washington Post reads. "The Order discriminates on the basis of national origin and religion. It closes our borders to the world's most vulnerable people, such as those fleeing the devastation of war. And it establishes discretionary and arbitrary rules for admission to this country, even by immigrants who have lived here lawfully for years."

The legal briefing argues that immigration and economic growth are "intimately tied," and that the order would damage the U.S.'s ability to attract the world's talent.

"Immigrants or their children founded more than 200 of the companies on the Fortune 500 list, including Apple, Kraft, Ford, General Electric, AT&T, Google, McDonald's, Boeing, and Disney, " it said. The briefing also notes prominent immigrant and refugee writers, scholars, and Nobel Laureates.

" Long-term, thisinstability [caused by the executive order] will make it far more difficult and expensive for U.S. companies to hire the world's best talent-and impede them from competing in the global marketplace," it says.

"The Court should hold the Executive Order unlawful," the draft concludes.

An estimated 37 percent of the workforce in Silicon Valley is foreign born, according to the think tank Joint Venture.