A coalition led by some of the world's biggest tech firms is taking on President Donald Trump's travel ban, signaling the contentious relationship between the sector and the White House could be about to get worse.
Scores of technology giants -- including Apple, Facebook, Google, Microsoft and Twitter -- filed a joint legal brief arguing against the temporary ban on refugees and travelers from seven Muslim-majority countries.
Tesla and SpaceX were among another 30 companies that added their names to the filing late Monday, pushing the total to more than 120.
Elon Musk, chief of Tesla and SpaceX, is on a Trump advisory group and it remained to be seen what siding against the president's order in court might mean to his role on that panel.
Uber founder Travis Kalanick quit Trump's business advisory board last week, saying he did not want to be seen as endorsing the president's policies.
The legal challenge suggests the important tech sector -- which overwhelmingly opposed Trump in the November election -- is likely to be headed for more battles with the new administration.
"The tech sector will stand up to the president when they see him threatening industry interests, and on the immigration issue all these companies depend heavily on foreign scientists and engineers," said Darrell West, director of the Brookings Institution's Center for Technology Innovation.
"I think there is likely to be an adversarial relationship because many tech companies are staffed by millennials, and dominated by young and progressive people who are opposed to what Trump is doing now."
While the sector enjoyed cooperation and access to the White House during the presidency of Barack Obama, West said that "the technology sector doesn't need much from government."
"Almost all the tech innovation is funded by the private sector," he added. "All they really want is a light regulatory touch."
The brief filed in a federal appeals court -- in support of a suspension of the travel ban -- said the order has already created disruption in the sector, which depends heavily on foreign-born talent.
"This instability and uncertainty will make it far more difficult and expensive for US companies to hire some of the world's best talent -- and impede them from competing in the global marketplace," said the brief endorsed mostly by companies in the technology industry with some non-tech firms such as Levi Strauss and yogurt maker Chobani.
It argued that highly skilled people "will not wish to immigrate to the country if they may be cut off without warning from their spouses, grandparents, relatives, and friends."
Companies backing the brief include Airbnb, Dropbox, eBay, Intel, Kickstarter, LinkedIn, Lyft, Mozilla, Netflix, PayPal, Uber, Yelp, Pandora, and HP Inc.
Executives from several top Silicon Valley companies previously spoken out against the ban, which temporarily closed US borders to all refugees and travelers from seven mainly-Muslim nations -- Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen.
Technology analyst Roger Kay of Endpoint Technologies Associates said the sector is fearful of Trump's intentions.
The travel ban has raised concerns, but "it's what that order heralds in terms of what's likely to come next," Kay said.
"The belief is that Trump hasn't even started warming up yet. He hasn't even gotten close to what he would like to do to the society. He's just firing a few warning shots."
Vivek Wadhwa, a tech entrepreneur who is a fellow at Carnegie Mellon University's College of Engineering at Silicon Valley, echoed those sentiments, saying Trump "showed that he could at his whim target any group he wanted."
"The fact that green card holders could be denied admission back into the country, that was the scariest thing possible," Wadhwa added, referring to the contradictory messages issued in the wake of the decree over the status of green card holders on foreign travel.
Bob O'Donnell, a Silicon Valley analyst and consultant with Technalysis Research, foresees more clashes ahead including on Trump's plan to tighten rules for the H1-B visa program for skilled workers and his vow bring manufacturing back to the United States.
Both of these issues are "huge potential concerns" for the tech industry, he said.
O'Donnell said most tech firms are loathe to cooperate with Trump, fearing it could hurt their image among his opponents -- and hit their bottom line.
"Companies are concerned about impacting their perception among their employees as well as their customers," O'Donnell said.
"They're trying to figure out how to distance themselves" from the White House.
But in some areas, he says, the two sides may be forced to work together, such as complex matters related to law enforcement access to encrypted devices.
"You can't put an executive order on encryption, there's way too much involved," he said.